What is Your Erdos Number and Network Science

On Friday, October 30, UMass Amherst had the pleasure of hearing Professor Albert-László Barabasi of Northeastern University speak on Network Science: From Structure to Control

This was a talk not to be missed. The talk was co-hosted by several entities at UMass including the Computational Social Science Institute (CSSI) ( a great group of colleagues with whom I enjoy being affiliated with). Room 150 in the Computer Science building was packed for his talk with an audience from many schools and colleges on our beautiful campus. My doctoral student, Shivani Shukla, and I represented the Isenberg School. Professor David Jensen of Computer Science introduced our distinguished speaker.


We had hosted Barabasi at the Isenberg School back in 2006 when I was on sabbatical at the Radcliffe Institute at Harvard in our great UMass Amherst INFORMS Speaker Series (and what an amazing list of speakers we had that Spring 2006, which even included Braess of Braess paradox fame).

I had last seen  Albert-László at a Network Science conference at the Media Lab at MIT, a few years ago,  to which I brought my doctoral student (now a Professor), Min Yu.

Barabasi began his lecture (I would have blogged it sooner but last week I was blogging from the INFORMS conference in Philadelphia and I was swamped) by bringing up Paul Erdos, a fellow Hungarian. Erdos,  the renowned mathematician,  had over 500 collaborators (some say 509 and others 511 - I have not counted them).  Erdos traveled the world from collaborator to collaborator with a suitcase typically staying for about 5 days.

Identifying one's Erdos number has become quite the hobby among STEM (and some other) folks. One has an Erdos number of 1 if one was a direct collaborator of Erdos', a number of 2, if one co-authored with a co-author of Erdos', and so on. My Erdos number is 4, by way of Paul Dupuis, Ofer Zeitouni, and Persi Diaconis.

You may be more familiar with the  Bacon number (named after the actor Kevin Bacon who starred in the move, "Footloose." 

And, of course, some actually know their Erdos + Bacon number.  Barabasi mentioned that his Bacon number was actually lower than his Erdos number, since he had been in a movie with someone who was in a movie with so and so and so on who starred with Kevin Bacon.

Now, what does this all have to do with Network Science?

Erdos is known for the Erdos-Renyi model in graph theory, which describes random graphs or networks. The degree distribution of the World Wide Web is not Poisson but follows the power law. Essentially, there are a very large number of small connected nodes in such a network and a few that are very highly connected. The World Wide Web is like an airline network with hubs. The Internet is a scale-free network according to the famous paper by yes, Faloutsos, Faloutsos and Faloutsos, but there has been some discussion about this claim.

Barabasi emphasized in his talk that a few actors are "hubs" and metabolic and protein interaction networks, which have evolved over 4 billions of years, also have hubs.

He noted that in network science (his books are definitely worth reading and he is highly cited), it is not just a matter of connecting nodes but that nodes are also evolving dynamically. He spoke of the preferential attachment model and then asked the question of where robustness comes from. He spoke about the Internet being robust to random failures and also noted that hubs are important both in the spread of ideas and diseases, as well. He referred to Vespignani, whom I have had the pleasure of meeting through the I3P association, which is a consortium based at Dartmouth.

His recent research, has, among many fascinating topics, been focusing on control. Just think of a car with 6,000 components but essentially only 4 are needed to control it. He also mentioned Kalman of Kalman filtering fame.

He described an interesting study that he conducted in Hungary in an organization to identify who were the hubs and found the 2 or 3 most influential people, one being the custodian, who was like "gossip central."

His talk was delivered with his fantastic energy, dynamism, and sense of humor. He included videos in addition to many vivid photographs. If you did not love networks before his talk, you would have fallen in love with them during it.

I was also very lucky to be invited to join Barabasi and a few colleagues from economics, computer science, and sociology (Professor James Kitts, who is the Co-Director of CSSI with Professor David Jensen). I also brought my husband along since he, like Barabasi, has a PhD in physics.


The discussions at dinner were fabulous. I wish that the evening would not end. We talked about topics as wide ranging as identifying Nobel prize winners from co-authorship of papers; determining through the language in an abstract whether a scientific paper was written by a female or a male, and we even discussed the Braess paradox.  I keep on emphasizing the importance of including flows and economic behavior of decision-makers in network science. We also discussed the success of the first PhD program in Network Science, which he helped to establish at Northeastern University and a similar PhD at a university in Hungary that he is affiliated with and that the billionaire Soros is helping to fund. Yes, Soros is also Hungarian.

below are photos taken at the dinner that great Friday evening.

Thanks to Professor Barabasi for coming out to Amherst from Boston and for your brilliant lecture on Network Science!

The Academic Family Tree Going Back to Maxwell, Newton, and Galileo

I always felt like I was standing on shoulders of giants in terms of outstanding researchers and scientists and, yesterday, my most recent Isenberg doctoral student to receive the PhD, Dong "Michelle" Li, surprised me with a truly special gift. Michelle is my 18th PhD student to receive the PhD.

She had my academic math genealogy tree printed through the Mathematics Genealogy project.

Typically, one is aware (obviously) of one's own PhD students and, of course, of one's dissertation advisor and probably knows of her or his advisor but how far back can you go? Below, I am with Michelle and her parents, both of whom are academics, and who traveled to Amherst for their first visit to the US to help Michelle in her move to assume an Assistant Professorship. Michelle and I are holding a poster of my academic family tree (ancestors and progeny).

Below is a photo of my academic family tree, which includes some renowned scientists such as James Maxwell, Isaac Newton, and Galileo, going back years, and operations researchers, more recently - Stella Dafermos and her advisor, Frederick (Tom) Sparrow.

Speaking of Maxwell, my academic great-great...-grandfather was looking over us when we were recently in Scotland to attend the EUROPT and EURO2015 conferences.

And, since the above photo of the academic family tree is hard to read, below I have included snapshots of the huge poster that Michelle presented to me. What surprises me is the list of academic ancestors that I have who received their PhDs from the University of Edinburgh or the University of Cambridge! Next spring I will be a Visiting Fellow at Oxford University so will have to stop by Cambridge to pay my respects.

 

 

 

It is quite amazing that operations researchers can trace their lineage to physicists but, then again, the father of operations research, Philip Morse, was a physicist!

And since I could not fit all of my PhD students into a readable photo the full list is here.

Just over 4 years ago, OR superstar and fellow blogger, Mike Trick, had a great post: Hello cousin!  In it he noted that we were actually cousins, academically related through Frederick (Tom) Sparrow, who was my advisor's (Stella Dafermos') advisor at The John Hopkins University. His post inspired my blogpost at that time.

Big Bang Theory in Berlin

I am attending a huge physics conference - about 6,000 participants in Berlin, Germany and am here since I was invited by Professor Scholl who organized this conference.

Professor Scholl heard me speak at a workshop on Energy and Complex Networks last summer in Erice, Sicily and extended the kind invitation.

I have enjoyed the talks very much since there are quite a few talks on network problems.

Today was the first full day of presentations and it began with an excellent presentation by Dr. Dirk Helbing from ETH Zurich. He spoke on A Planetary Nervous System to Understand and Measure Our Society. I had last seen Dirk two Septembers ago at a terrific Risk Management Workshop in Zurich, Switzerland, at which we both spoke.

Dirk recorded his presentation this morning and said that it should be posted on Youtube in about 2 weeks.

At the end of the day I immensely enjoyed Dr. Duncan Watts' presentation: Computational Social Science: Exciting Progress and Future Challenges.

The talks here are very interdsciplinary, which I like very much. For example, Watts of small world fame, is a sociologist, who received his PhD from Cornell, and was at Columbia but is now with Microsoft in NYC.

His talk had two parts: the first focused on Twitter and the kind of analyses that he has been doing of rare events - messages that go viral. It was fascinating to learn that about 93% of Twitter posts never get retweeted even once. Those who get retweeted 100 times or more are a small fraction of tweets. He analyzed the network structure of such tweets, which are rare events, and require a huge sample for statistical purposes. He found that some viral tweets have a broadcast structure with the media playing a very important role. He said that if you want your message to spread write an OpEd and get it published in The New York Times. Of course, he noted that Justin Bieber and Katy Perry have 15 million followers so, in effect, that act as broadcasters, very often of images and videos (some of themselves).

In the second part of his presentation he spoke on Crisis Mapping, a project that he has worked on with the United Nations and also using Mechanical Turk.  This really interested me since I am teaching a course on Humanitarian Logistics and Healthcare. He was conducting research to map tweets during a disaster for the United Nations to get information about the disaster. He compared the information gleaned during a disaster versus using the same data but having individuals working in groups using Mechanical Turk. He found some unexpected results in that the larger the group the answers were not necessarily better.

Many of the researchers at this conference are interested in socio-economic phenomena and associated problems. I appreciate the methodologies that are being used and the scope of issues that physicists and the like are tackling.

Tomorrow morning I have the pleasure of introducing Dr. Luis Bettencourt of the Santa Fe Institute when he gives his invited talk on cities.

I will be speaking Wednesday morning.

It has been wonderful spending my spring break at this great conference in stately Berlin!

In at the Beginnings with Philip M. Morse, the Father of Operations Research in the U.S.

I very much enjoyed the plenary lecture that the Morse Award winner Professor Dimitris Bertsimas of the Sloan School at MIT gave at the San Francisco INFORMS Meeting this past November. Paul Rubin wrote a nice blogpost on it. In his lecture, Dimitris noted that he, from time to time, rereads the autobiographical book by Philip M. Morse, after whom the award is named. The book is, "In at the Beginnings: A Physicist's Life" and it was published by MIT Press in 1977.

So, during this winter break, while revising a paper and finishing up two papers, after the holiday celebrations, I  found time to read the book, which my husband had a copy of. My husband has a PhD in physics, as did Morse. The below photos are taken from the book and I was excited to see one female featured but that was at a ceremonial dinner of the Japanese Union of Scientists and Engineers (JUSE).

 

 

 

Morse was born in 1903 and, after receiving his PhD from Princeton in 1929, joined the physics faculty at MIT.  He was drawn to Operations Research (OR) during World War II. The title of Morse's book is perfect, because he was truly at the beginnings of many important organizations and events, from the establishment of the Anti-Submarine Warfare Operations Research Group during World War II to the founding of the Operations Research Center at MIT.

I had met Philip Morse when my husband and I were grad students at Brown University and Professor Bob Beyer, of acoustics fame, invited us to a reception of the Acoustical Society, which was having its meeting in town and we were introduced to Morse. Interestingly, my industrial jobs, while pursuing my Master's in Applied Math at Brown, were in technical consulting for the naval submarine sector in Newport, Rhode Island.  My very first project involved developing software in AN-UYK assembly language for submarine transiting so that the enemy would not be able to detect the submraines via sonar. Hence, I enjoyed the chapters of the Morse book that described the scientific challenges of the wartime efforts.

Reading his autobiography was very special, I must say. I am also a big fan of the Operations Research Center at MIT since I had an NSF Visiting Professorship there and organized a speaker series to bring outstanding females in OR to speak.

Morse was an amazing scientist, contributing to both physics and to the, at that time, still young, but growing, discipline of Operations Research, which he was passionate about and used his extensive network of friends and contacts to promote, whether in Washington or in Europe (including NATO and the OECD).  He wrote glowingly about the founding of IFORS, the International Federation of Operations Research Societies, and its first meeting in 1957 in Oxford, followed by the conference (very successful) in Oslo. Also, Morse was the first President of ORSA, the Operations Research Society of America, the precursor to INFORMS. His doctoral student, John D.C. Little, renowned in OR, wrote a nice tribute in his honor, that was published in the journal Operations Research  on its 50th anniversary.

I enjoyed reading about how Morse was instrumental in promoting computers at MIT in the 1960s and also the challenges that he faced but, nevertheless, the Computation Center was established. I was delighted to hear him mention the role that Marvin Minsky played, who was then a young mathematician in computing and who was to become the founder of artificial intelligence. His daughter, Margaret, is a neighbor of mine in Amherst and his son and my daughter graduated Deerfield Academy together. I saw Marvin last time at the graduation festivities.

In his autobiography, Morse talks about the joys of teaching and of conducting research. On page 66, he states: "the devising of a new theory, or even the extension of a known one, is exploration, with all the excitement and trials and false starts and effort of any exploration. It is somewhat like putting together an intricate jigsaw puzzle."

On page 119, he write: "I have always learned new subjects quickly; perhaps breadth rather than depth was best for me. .. Perhaps the most interesting life results from following one's interests, wherever it leads, rather than by assuming some rigid set of obligations, self-imposed or set by others." Morse was an explorer in the truest sense of the word.

Morse was a voracious reader, reading 4 to 5 books a week, with many in the humanities. He considered his books, both those in physics and in operations research, as some of his greatest publications.

Another favorite quote from the book appears in page 318: "The delights of research in O/R (he used the slash) are multiple. To me the pleasure coming from understanding how traffic behaves is as great as that coming from understanding how two atoms combine. In addition, the practical applications of O/R theory are often immediate and satisfying." I could very much relate to his fascination with traffic, a research topic that I have pursued since my graduate days at Brown working with Professor Stella Dafermos.

In the next to the last chapter of the book, he writes about a request by the National Academy of Sciences in January 1962 by President John Kennedy to "evaluate and recommend research on behalf of the conservation and development of America's natural resources." The ultimate report identified 10 recommendations, including: to conduct research on pollution and its effect on man's total environment. However, once the report went through the review and publication processes, the President had been assassinated and the world had lost its stability.

The final chapter ends with the following beautiful lines: "For those who like exploration, immersion in scientific research is not unsocial, is not dehumanizing; in fact, it is a lot of fun. And, in the end, if one is willing to grasp the opportunities, it can enable one to contribute something to human welfare."

And physicists and operations researchers continue to tackle some of the most challenging problems today whether in terms of energy, pollution, or even healthcare.

In March,  I will be speaking in Berlin on "Design of Sustainable Supply Chains fr Sustainable Cities," at the Symposium (SOE/DY) Physics of Sustainability and Human-Nature Interactions, upon the invitation of physicists.

Professor Morse's legacy lives on through all of us.

Terrific Operations + Analytics Conferences in 2015 + More!

I am very much looking forward to the New 2015 Year!

The Spring 2015 semester I will be teaching two of my favorite courses at the Isenberg School and the Supernetwork Center Associates and I will be taking part in many conferences.

Shortly after the 1st of the New Year, there will be the 2015 INFORMS Computing Society Conference in Richmond, VA, January 11-13, at which we will be presenting our latest work on our NSF Future Internet Architecture project. The title of our paper is: A Game Theory Model for a Differentiated Service-Oriented Internet with Duration-Based Contracts, Anna Nagurney, Sara Saberi, Tilman Wolf, and Ladimer S. Nagurney. The paper will be published in the Proceedings of ICS 2015. Sara is one of my doctoral students who is also a 2014 Isenberg Scholar.

Then, on February 7, 2015 (no travel needed for us for this one for us), the second Women of Isenberg Conference will take place at, of course, the Isenberg School of Management! I have been asked to speak on the Building Your Brand panel. This should be very engaging and fun and no power point is needed! Last year I enjoyed the inaugural Women of Isenberg conference very much  and blogged about it. It was extra special to see one of my former undergrads and Supernetwork Center Associates, Christina Calvaneso there. Christina was funded, in part, under one of my NSF Research Experiences for Undergraduates (REU) grants.

Later in February I will be going to a conference in Florida: World Congress on Global Optimization: WCGO 2015, Gainesville, FL, February 22-25. There I will present work with one of my doctoral students, Dong "Michelle" Li:: Supply Chain Performance Assessment and Supplier and Component Importance Identification in a General Competitive Multitiered Supply Chain Network Model. By that time I suspect, given last year's fierce winter in New England, I will need to see some greenery and experience some warmer temps!

In March, 2015, to coincide with my Spring Break, I will have the pleasure of speaking in Berlin, Germany. Last summer I was an invited speaker at a workshop in Erice, Sicily on energy, and a member of the audience liked my presentation so the good word spread. I will be speaking in Berlin on "Sustainable Supply Chains for Sustainable Cities." The conference should be very interesting. It  is on Φ·SOE Fachverband Physik sozio-ökonomischer Systeme (Physics of Socio-Economic Systems Division), German Physical Society, March 15-20. So nice to see my name on the elegant conference flier! Danke schon!

(Some folks like to present the same talk at multiple venues - I like to present different talks!)

In April, 2015, it will be time for the INFORMS Conference on Business Analytics and Operations Research, Huntington Beach, CA, April 12-14. I had such a marvelous time last year at the Boston Analytics conference, at which I spoke on Cybersecurity and Financial Services, that I had to submit a proposal to speak in CA. We'll see if the proposal is successful! Center Associates Professor Jose Cruz of UConn and Professor Zugang "Leo" Liu of Penn State Hazleton will both be going to this conference.

In early May, to coincide, inconveniently, as also happened last year, with our UMass graduations,  the POMS conference will take place in DC. All of my doctoral students and I have submitted papers for presentation there and I have another one submitted with a former student who is a Center Associate, Dr. Min Yu of the University of Portland.

Once the semester is over with, there will be more travel, of the international kind. I am a co-organizer of the conference, 2nd International Conference on Dynamics of Disasters (DOD 2015)
Kalamata, Greece, June 29-July 2, 2015, which should be outstanding (but I am a bit biased, I must say). The Organizing Committee consists of academics and practitioners from around the globe.In Spring 2015 I am again teaching my course, Humanitarian Logistics and Healthcare, so the conference will be very synergistic.

Then it will be time for the EURO XXVII Annual Conference, Glasgow, Scotland, July 12-15,  My great colleague and Supernetwork Center Associate, Professor Patrizia Daniele, invited me to speak in her session, which will also have Professor Tyrrell Rockafellar as a speaker. He is renowned for his work in optimization!

Faculty and even doctoral students are jet-setters but conferences are extremely important venues for knowledge exchange and, of course, networking! Plus, one's institution gains from the enhanced visivility!

The Serendipity of Science and Why Dreamers are Important - Nobel Laureate Sheldon Glashow at UMass Amherst

Yesterday, we had the pleasure of hearing Dr. Sheldon Glashow, a Nobel laureate in physics speak on "A Parable of the Pure and the Practical," at UMass Amherst.

When I saw the announcement for his talk, which was quite provocative and which is reposted below, I knew that the talk would be great:

Politicians and opinion makers argue stridently that governments and universities should invest only in such areas of research that are likely to result in immediate and specific benefits, through wealth enhancement or job creation. They find undirected curiosity‐driven research in basic science to be useless and unaffordable luxuries that consume resources rather than promoting economic growth and human welfare. 

This talk will show how wrong they are.

Dr. Glashow was inspiring, entertaining, and very energetic and he spoke to a standing room only crowd. He mentioned that this was only the second time he was giving this lecture - the first being in China.

He quoted from Louis Pasteur: "Chance favors the prepared mind," and demonstrated the role that serendipity plays in scientific discoveries. Researchers are trying to do something but find something else from saccharine to velcro, to teflon, to even Viagra (lots of chuckles from the audience).

He emphasized that dreamers are important and that many Nobel prize discoveries where, at first, useless.  He showed through numerous examples - I took photos of some of his slides, which I have posted below, because I could not write fast enough in my notes - that curiosity-driven searches are as effective as directed ones. He also noted technology transfers and that these may take years but without the discovery of DNA structure we would not have gene therapies, without general relativity we would not have GPS systems, and noted that radioisotopes saved his life. This reminded me of the medical nuclear supply chain work that we have published several papers on.

One has to "keep one's eyes wide open" for those accidental discoveries. Think of Kevlar, for example.

I also VERY MUCH appreciated his emphasis of the importance of international collaborations because that is fundamental to our work at the Virtual Center for Supernetworks at the Isenberg School at UMass! He also related his fond memories of his high school in NYC, the Bronx High School of Science, which has produced more Nobel laureates than any high school on the planet - 7 in physics and 1 in chemistry (he did share a lot of jokes about chemists).

You can click on the photos below to enlarge them.

Remember the importance of the scientific method and the prepared mind!

Dr. Glashow also mentioned that his sister-in-law was Lynn Margulis, a former UMass faculty member, who passed away not long ago. I thanked him for his brilliant lecture afterwards and we reminisced about NYC. You could tell that his sense of wonder about the universe has never left him, which is truly special!

And, speaking of those great old school ties, Dr. Glashow was introduced by his former classmate at the Bronx High School of Science, Professor Morton Sternheim, who, along with his wife, has endowed this lecture series.

Defying Gravity and Success is the Best Revenge - Nurturing STEM Talent in Our Students, Females and Males

The article by Eileen Pollack in The New York Times, Why Are There Still So Few Women in Science? is a must read. Eileen was one of only two females to receive an undergrad degree in physics from Yale in 1978 and writes eloquently about her experiences and those of other females then and more recently in the pursuit of studies in STEM (science, technology, engineering, and math) fields. She asks a fundamental question as to why still in the new millennium there are so few women in science and math. The conclusion reached in her very thoughtful and well-written article, filled with highlights from various studies as well as personal stories, is that it is the culture and the lack of support and mentorship.

She ends her aticle by describing a picnic back at Yale recently at which there were several female grad students (it was a picnic for the physics and astrophysics departments) in which there were a few female grad students including one African American.  Pollack concludes as follows:
 

The young black woman told me she did her undergraduate work at a historically black college, then entered a master’s program designed to help minority students develop the research skills and one-on-one mentoring relationships that would help them make the transition to a Ph.D. program. Her first year at Yale was rough, but her mentors helped her through. “As my mother always taught me,” she said, “success is the best revenge.” 

As so many studies have demonstrated, success in math and the hard sciences, far from being a matter of gender, is almost entirely dependent on culture — a culture that teaches girls math isn’t cool and no one will date them if they excel in physics; a culture in which professors rarely encourage their female students to continue on for advanced degrees; a culture in which success in graduate school is a matter of isolation, competition and ridiculously long hours in the lab; a culture in which female scientists are hired less frequently than men, earn less money and are allotted fewer resources.

The above speaks to resiliency and the role that, we, as educators, have in nurturing talent and confidence in our students, both females and males alike, in technical fields.  I teach in a business school but have 3 degrees in Applied Math, with a PhD in the specialty of operations research.  I love math, computer programming, and the applications that our tools and methodologies can help to formulate and solve from transportation to financial services to healthcare to logistics and supply chains. I have written about gender inequality in business schools as well.

A kind sentence can make a difference in a student's life and can give her (or him) the confidence to believe in her or himself and to pursue  advanced degrees and careers in areas where you may stand out (this may have some negatives, at first, but people will remember you).

My seventh grade math teacher, Mrs. Fuller, back in Yonkers, NY, said to me, "One day you will be a calculus professor." That statement has stayed with me to this day as have those that have said: "Anna, being a professor is the loneliest profession," and "Anna, the higher you rise, the greater of a target you will be." The latter two were by two of my male professors at Brown and there is wisdom in both statements, which I appreciate.

And culture is clearly so important so we need to increase the visibility of female scientists, engineers, and also business professionals and scholars. The Times article noted the rather stereotypical representation of female scientists and females in the TV series Big Bang Theory.

Let me give you a VERY cool and REAL example of a top female scientist, whom I had the pleasure of meeting at the UMass Rising gala event last April that I wrote about -- the astronaut Dr. Cady Coleman. Cady received her undergrad degree from MIT and her PhD from UMass Amherst in polymer science and engineering.

The photo of Cady and me below was taken at the UMass Rising gala. Cady lives in western Massachusetts with her husband and son when not training and flying in outer space. She was one of the Masters of the Ceremony (along with Ken Feinberg).

There was an article yesterday in our local newspaper, the great Daily Hampshire Gazette (DHG), about Dr. Cady Coleman and how she consulted with Sandra Bullock on the movie Gravity, which will be released today and which also stars George Clooney. She was also featured in Mother Jones with the full article here as well as in Wired. 

In the DHG article, Cady states: I think it's an especially good film for girls. They need models of strong, courageous women who may not always know what to do, but can figure it out. I liked it, in that respect.

 So do be positive with your students -- a few words that recognize talent and an achievement can change a direction of a life!

3 Great Books by 3 Great Females

Usually, when I am writing a book, I am so focused that I don't read other books during that period.

This year, our Networks Against Time book was published and I heard the other day from a Springer editor, who is also a UMass Amherst grad, that it will be on display at the INFORMS conference in Minneapolis, which is exciting!

 

Once our book was out and, since I was on sabbatical this year, it was time for some reflection,  and that involved reading several books that I was quite interested in because of their authors.

I write nonfiction -- books on network themes from transportation to supply chains to supernetworks and I am also drawn to nonfiction books, from those of a technical and professional nature to  memoirs and, lately, to memoirs by women. One can get valuable advice from the latter volumes and compare your professional and life situation to those of others.

The 3 books that I recently read  (my summer reading, in part) are displayed in the photo above, which also features some lovely craft pieces received as gifts from a former doctoral student of mine, which are from the village in his home country.

Yes, I had to read Sheryl Sandberg's Lean In, given all the media attention and commentaries on it,  and was very interested to see whether or not it would "speak" to me as an academic, who also has had several years in industry in high tech consulting for the defense sector. Many pages of Lean In I marked with colorful Post-it notes. Sheryl, the Chief Operating Officer of Facebook,  spoke very honestly, in my opinion, of the challenges that she faced even with such mentors as Dr. Larry Summer, the former President of Harvard, whom I met as a Fellow of the Radcliffe Institute for Advanced Study. 

I would love to hear back from female academics who have read this book to see what their opinions of it are!

Fay Ajzenberg-Selove's book, A Matter of Choices: Memoirs of a Female Physicist, I became aware of through an obit written by Gloria Lubkin, which appeared in Physics Today. I had met Lubkin at Brown University through a physics professor there, the great Bob Beyer, who introduced me and my husband, a physics doctoral student at that time, to her. In the obit, she recommended this book, and I was intrigued and loved it! Fay was a trailblazer, who never gave up. One of my favorite paragraphs from her book:

If you work on interesting science, it is essential to schmooze with other scientists in your research field, and find out what they are doing at the time they are doing it. Your own work will not be current if you wait until your colleagues' results are published, since this occurs at least several months after the work is completed. Attending meetings is essential. The meetings take place at venues throughout the world. They are organized in such a way that no group has a recurring burden, nor a disproportionate influence, in running them. It is part of the fun of physics, and of science generally, that its practitioners become world travelers, well acquainted with international airports and with watering holes.

Although Fay could never have children, she had a long, loving marriage and her scientific community was her extended family and did she socialize!

Anna Quindlen, the Pulitzer Prize winning author (for commentary) and former columnist,  has authored many books, including novels. As a mother of 3 out of college children, she, typically, wrote and still does from 9AM until 3PM and her book, Lots of Candles, Plenty of Cake, I very much enjoyed.

Anna Quindlen spoke at a ceremony in NYC at which I received a Young Achiever's Award  from the National Council of Women of the United States, Inc., a few years after my receipt of a PhD from Brown University. In her book, she speaks on the importance of friendships, lending a hand to others, and how far women have come, among several other themes that any female can relate to. I especially enjoyed the afterword in which Quindlen engages in a conversation with her friend, Meryl Streep.

The Most Multidisciplinary Supply Chain -- The Medical Nuclear Supply Chain -- Where Operations Research, Physics, Chemistry, and Biology All Meet

Supply chains underpin our economy and are part of each and every industry.

To model and solve supply chain problems, one often has to take a multidisciplinary approach.

Never more so than in the case of medical nuclear supply chains, a topic that we have been researching for several years now and have even written an OpEd piece . These supply chains are especially vulnerable due to the aging of the nuclear reactors where the isotopes are irradiated. Each day, 41,000 nuclear medical procedures are performed in the U.S. using Technetium-99m, a radioisotope obtained from the decay of Molybdenum-99. The Molybdenum is produced by irradiating Highly Enriched Uranium (HEU) targets in research reactors. The radioisotopes are used in medical imaging and diagnostics ranging from cardiac problems to cancer.

When I was an undergraduate at Brown University, and then a graduate student there, I remember being told that one might make use of subject matter in the future that one was studying even though it might not be apparent or even envisionable at that point.

I especially enjoy working on systems, notably, network systems, and, hence, my love of supply chains.

I would argue that medical nuclear supply chains are the most multidisciplinary supply chains and to capture their functionality (and, of course, vulnerability) and, hence, to improve their operation as well as their design, one has to be knowledgable about physics, chemistry, biology/medicine, and, of course, operations research. This may entail collaborations across disciplines but that is an approach that pushes knowledge forward.

Above we have composed a graphic that highlights some of the salient issues surrounding medical nuclear supply chains. Our most recent paper on the topic is: Securing the Sustainability of Global Medical Nuclear Supply Chains Through Economic Cost Recovery, Risk Management, and Optimization, Anna Nagurney, Ladimer S. Nagurney, and Dong Li, to appear in the International Journal of Sustainable Transportation. An earlier paper of ours: Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach, Anna Nagurney and Ladimer S. Nagurney, was published in the International Journal of Production Economics 140(2): (2012) pp 865-874.

A lecture given on the topic to biomedical engineers, which has additional background material, can be accessed here.  Another nice lecture on prezi, which cites our work, and has stunning graphics, can be viewed here.

Hence, do listen to your professors -- chemistry, physics, biology, and math, and operations research you may one day be using and applying and even integrating!

When the Most Recent Time Feels as Good as the First Time -- Getting a Paper Accepted and Published

I recently received an email message from a former doctoral student of mine that is the kind of message that is a keep-sake. It highlighted milestones in an academic career.


The message included the following, which had been copied to several former and present doctoral students of mine.

When I received your phone calls in my dorm at China, I didn't realize that's one of the biggest decisions in one's life. From the first day at UMASS, the first presentation at Professor's 821 class, the first homework that I ever graded, the first paper, the first conference, the first job interview, the first job offer,...until now the tenure and promotion, every step in my growth records Professor Nagurney's effort. I can't thank you enough, Professor!

I met my best friends in the supernetwork lab which is really like a family. Thank you all for friendship and support, which is my lifelong asset!~~~

This got me thinking -- I hope that, as an academic, one never loses that sense of wonder and, indeed, happiness, at getting another paper accepted for publication and then seeing it in a journal.


Do you recall the time that you received the good news of the acceptance of your first journal article?


My first three journal articles were co-authored with my doctoral dissertation advisor at Brown University, Professor Stella Dafermos, the second female in the world to receive a PhD in Operations Research. We actually had, as our first set of joint publications,  a series of three papers, published, in Mathematical Programming, Transportation Research B, and in Operations Research.

That same year (and only a year after receiving my PhD), I then had a single-authored paper (another first) published in Transportation Research B.

Last week, we heard the good news that a paper that I had written with the other Dr. Nagurney, who is educated in physics, had been accepted for publication. The effort in understanding the scope of the medical nuclear supply chain network problem and issues, which are affecting medical diagnostics, and even security, along with acquiring the data for the problem, had been intense, and, after two revisions, we had done it. The paper integrates operations research and physics for a supply chain network application.

The good news of the paper acceptance made our day and the warm feeling continues and makes the hard work worth it.


I hope that I never lose that feeling -- and wish you all the same.

Isaac Newton's Tree Lives On as Does the Academic Family Tree

My husband, who has a PhD in physics from Brown University, shared with me today that department's annual 2011 newsletter and, in particular, a fabulous article on Isaac Newton, his discovery of gravity, falling apples, and even the bubonic plaque and the role that it played (or legend has it) .

The article is featured above with the photos, compliments of the newsletter.

What is truly amazing, is that there is an apple tree outside of the Barus and Holley (B&H) building at Brown University in Providence, Rhode Island, that has a graft of a tree that was a descendant of a tree from Newton's orchard! I had my office in B&H when I was a graduate student in Applied Math at Brown, specializing in Operations Research.

Every year, Professor Humphrey Maris distributes the fruit from this apple tree to his physics students in order to inspire them.

According to the article: On October 7, the Physics Department gathered to commemorate the legendary fall of an apple. A dozen years ago, Humphrey Maris planted a graft of a descendant of the apple tree believed to have inspired Sir Isaac Newton’s universal law of gravitation. The tree, located near the steps of Barus & Holley, is an antique strain called “Flower of Kent.” Each fall, Professor Maris harvests the fruit it bears to share with his students.

Legend has it that the bubonic plague played a peripheral role in Newton’s seminal moment. Newton was a student at Trinity College in Cambridge when the plague swept across Europe, reaching Cambridge in 1665 and forcing the university to close. He returned to Woolsthorpe Manor, his family’s home in Lincolnshire,
England, where he observed apples falling in the garden.

I had earlier written that I could trace my academic genealogy back to Newton, with the help of Professor Mike Trick's great research.

Nice to know that we can not only go back to Newton in terms of our academic lineage and academic family tree but also forward in terms of Newton's apples!

Our OpEd on Medical Nuclear Supply Chains Published Today

It is important not only to do research but also to speak about it at conferences and at other forums.

There are also topics that one may feel sufficiently passionate about and may wish to disseminate thoughts, ideas, and even research results on to a broader audience. Hence, it is also important for academics to contribute OpEd pieces to newspapers on timely topics.

Medical nuclear supply chains, which impact our healthcare security, are such a topic and their vulnerability needs to be addressed.

There is some movement in the US Congress in this direction but the criticality of such supply chains, which enable both cardiac and cancer diagnostics, needs to be emphasized.

Our OpEd piece on the subject: Viewpoint: Passage of American Medical Isotope Production Act of 2011 will help ensure U.S. nuclear medicine supply chain, was published in today's Springfield Republican newspaper, and may be read here.

We have begun to conduct serious research on the design and redesign of medical nuclear supply chains. Our first study on the subject can be accessed, in pdf format, here.

Medical Nuclear Supply Chains -- Where Physics Meets Operations Research for Healthcare Security

I came across an interesting presentation given to a pharmaceutical audience on medical nuclear supply chains in which my book, Supply Chain Network Economics, was cited.

This topic very much intrigued me so I began to research it.

For some background:

Each day, 41,000 nuclear medical procedures are performed in the United States using Technetium-99m, a radioisotope obtained from the decay of Molybdenum-99. The Molybdenum is produced by irradiating primarily Highly Enriched Uranium (HEU) targets in research reactors. Surprisingly, for over two decades, no irradiation and subsequent Molybdenum processing has occurred in the United States. All of the Molybdenum necessary for our nuclear medical diagnostic procedures, which include diagnostics for two of the greatest killers, cancer and cardiac problems, comes from foreign sources. Since Molybdenum-99 has a half-life of only 66.7 hours, continuous production is needed to provide the supply for the medical procedures. Thus, the US is critically vulnerable to Molybdenum supply chain disruptions that could significantly affect our healthcare security and is completely at the mercy of foreign suppliers.

Currently, about 60% of the supply of Molybdenum-99 (Mo-99) for the United States comes from a Canadian reactor, with the remainder coming from Western Europe, with its production taking place in Western Europe, the former Eastern-Bloc States, and South Africa. Worldwide, there are only 9 reactors used for the target irradiation and only 6 major processing plants. The shutdown of any of the reactors or processing plants, due to routine maintenance, upgrades, or, as occurred during 2009 and 2010, for emergency repairs, could significantly disrupt our Molybdenum supply and impact our medical facilities' abilities to perform the necessary imaging for cardiac and cancer diagnoses. The number of processors that supply the global market, however, is only four, and they are located in Canada, Belgium, The Netherlands, and South Africa. Australia and Argentina produce bulk for their domestic markets but are expected to be exporting smaller amounts in the future.

Limitations in processing capabilities restrict the ability to produce the medical radioisotopes from regional reactors since long-distance transportation of the product raises safety and security risks, and also results in greater decay of the product. The number of generator manufacturers, in turn, with substantial processing capabilities, is under a dozen. In addition, several of the reactors currently used, including the Canadian one, are due to be retired by the end of this decade, with the majority of them being between 40 and 50 years of age.

Moreover, although most of the current production of Mo-99 uses HEU targets, all producing countries, where economically and technologically feasible, have agreed, in principle, to convert to low enriched uranium (LEU) according to the latest OECD Nuclear Energy Agency (2011) report. However, although the use of LEU targets for Mo-99 production has advantages over HEU, with proliferation resistance (and, hence, enhanced global security) being a primary one, along with easier availability of the target material and also easier compliance for its transportation and processing, the negatives, nonetheless, include: a lower production yield than HEU and a greater number of targets needed to be irradiated with associated increased volumes of waste. Hence, both production and processing pressures are raised as well as waste management issues.

Since Mo-99 decays with a 66.7 hour half-life, approximately 99.9% of the atoms decay in 27.5 days, making its production, transportation, and processing all extremely time-sensitive. In fact, its production is quantified in Six-day curies end of processing denoting the activity of the sample 6 days after it was irradiated to highlight this. In addition to the time-sensitivity, the irradiated targets are highly radioactive, significantly constraining transportation options between the reactor and the processing facilities to only trucks that can transport the heavily shielded transportation containers. While the extracted M0-99 continues to be constrained by its decay, its shielding requirements are reduced, allowing for transportation by modes other than trucks, including by air.

So what did we do?

We began to identify what a rigorous medical nuclear supply chain network model for this radioisotope should include.

For example, a proper model of this critical medical nuclear supply chain, which allows for appropriate economic cost quantification, heavily emphasized by policy-makers, must include the physics-based principles of the underlying radioactivity, and must incorporate multicriteria decision-making and optimization to capture the operational and waste management costs as well as risk management, subject to constraints of demand satisfaction at the hospitals and medical facilities. Moreover, it must be sufficiently flexible and robust in order to provide rigorous solutions as the technological landscape changes. Furthermore, it should enable the redesign of the supply chain network.

With the creation of such a medical nuclear supply chain network economic optimization model, decision-makers, policy-makers, as well as, healthcare providers, would have the ability to analyze the medical nuclear supply chain vulnerabilities, and synergies, as well as to explore the relevant costs and risks. In addition, the effects on costs and risks of changes in demand, which is expected to increase given the aging population, could be assessed. Moreover, the various stakeholders including the government, the medical firms, and the hospital and imaging facilities, through such a supply chain network economic optimization model, could determine the true costs of operating the reactors, and the same holds for the processing facilities, as well as the generator manufacturing facilities. Such a transparent framework would enhance healthcare security, would allow for more accurate pricing and cost recovery, and would enable the evaluation of disruptions to the medical nuclear supply chain.

We have developed such a model, which is a generalized network model, along with an algorithm, in the paper, Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach, which may be downloaded at:
http://supernet.som.umass.edu/articles/Medical_Nuclear_Supply_Chains.pdf

This paper, I co-authored with my husband, Professor Ladimer S. Nagurney, who holds a PhD in physics, so it represents a true meeting of physics and operations research.

I will be presenting this paper later this month at the Seventh Conference on Integrated Risk Management in Operations and Global Supply Chains. This year, this conference is being hosted by the Desautels Faculty of Management at McGill University, in Montreal, Canada, July 31st - August 1st, 2011. The goal of the conference is to bring together leading academic researchers and practitioners whose work strives to meet at the intersection of Finance, Economics, Operations, and Supply Chain Management. The conference web site is http://intrimatmcgill.wordpress.com.

According to the conference announcement, this two-day conference will feature a single track of presentations that combine technical presentations, industry practices, and discussions on relevant challenges and approaches in the topic area. There will be sixteen 90-minute sessions. Each session has two 30-minute presentations, followed by a discussant giving an overview of related research as well as facilitating a discussion with session participants. The format aims to stimulate discussion and interaction among speakers and participants.

I am very much looking forward to this conference and to presenting our work on medical nuclear supply chains.

Wonderful Videos on the Science of Winter Sports, the Olympics, Thanks to NSF and NBC News

The National Science Foundation, with NBC News, has produced a series of wonderful videos of winter sports, with a focus on last year's Winter Olympics in Vancouver, and the science behind the sports.

I especially appreciate the videos on figure skating (yes, my daughter is a figure skater, and also plays on a couple of varsity sports teams); the material science behind skates from the boots to the blades and how they differ for speed skates, hockey skates, and figure skates, and the math behind sports. These short videos include faculty speaking on their research in sports. Several faculty from Ithaca College, Cornell University, and Williams College (the host of the recent Bay State Games) give great deliveries of their work, to name just a few. You can see such athletes as Apollo Ohno and Rachel Flatts, to name just two, in the videos.

And for all of the skiers out there, there are several videos focused on skiing, just for you!

These videos are engaging, informative, and very well-done, so enjoy! I even heard "optimization" mentioned in the context of sports, which was great to hear!

You can access all the Science of the Winter Olympic Games videos here.

Mark Newman Speaks on Networks at UMass Amherst

I attended a very enjoyable colloquium yesterday in the physics department at UMass Amherst given by Professor Mark Newman of the University of Michigan and the Santa Fe Institute.

The title of his talk was: Epidemics, Erdos Numbers, and the Internet: The Structure and Function of Complex Networks

Abstract: There are networks in almost every part of our lives. Some of them are familiar and obvious: the Internet, the power grid, the road network. Others are less obvious but just as important. The patterns of friendships or acquaintances between people form a social network; the species in an ecosystem join together to form a food web; the workings of the body's cells are dictated by a metabolic network of chemical reactions. As large-scale data on these networks and others have become available in the last few years, a new science of networks has grown up, drawing on ideas from physics, math, engineering, biology, and other fields to shed light on systems ranging from bacteria to the whole of human society. This talk will examine some new discoveries regarding networks, how those discoveries were made, and what they can tell us about the way the world works.

I had hosted Professor Newman several Octobers ago, when Professor David Parkes and I organized an Exploratory Seminar on Dynamic Networks at the Radcliffe Institute for Advanced Study at Harvard, so it was nice to see him back in Massachusetts.

Some of the network images that he used in his talk yesterday are available here.

His audience yesterday was comprised of physicists, engineers, and computer scientists and yours truly (plus some folks I could not name nor did I know their backgrounds).

His talk (with a wonderful delivery and enthusiasm) focused mostly on network structure, whereas my research focuses on a wide spectrum of networks where flows and user behavior matters, in addition to network structure, from supply chains to transportation networks and the Internet as well as economic and financial networks and electric power networks. He mentioned food webs which I could relate to since my work in network economics is being applied to fisheries. I told him afterwards that I would like to see more work in social networks that includes flows (as the work that I did with my former doctoral student, who is now a Professor, Dr. Tina Wakolbinger, does).

Also, as I tell my students, we in operations research/management science and even in economics can trace the literature on the subject even back to the mid1800s! Networks in terms of model formulations, applications, and even methodologies and algorithms have been major topics of scientific research especially beginning with the 1950s and beyond. The fascination with networks and novel applications have made the subject seem "new" to some and especially to disciplines, who have more recently discovered networks and are applying tools from their disciplines to their study.