Richard Brualdi at AIM

2010 NSF-CBMS Regional Conference
The Mutually Beneficial Relationship of
Matrices and Graphs

July 12-16, 2010

Principal speaker:
Prof. Richard Brualdi, University of Wisconsin-Madison

Iowa State University
  supported by the National Science Foundation through DMS 0938261
and by the Institute for  Mathematics and its Application (IMA) through its Participating Institution (PI) Program.

ISU Department of Mathematics




Richard Brualdi, University of Wisconsin-Madison, was the principal speaker.  He is one of the founders and continuing leaders of the area of Combinatorial Matrix Theory, author of more than 200 papers,  and an award-winning teacher.  The conference was organized by Leslie Hogben, Iowa State University, and Bryan Shader, University of Wyoming.

The conference discussed the symbiotic relationship between matrices and graphs and the significant role that they jointly play in pure and applied mathematics, science, and technology.   In addition to Prof. Brualdi's lectures (held during the mornings), this conference offered collaborative (AIM-style) research groups with leading experts in combinatorial matrix theory (meeting in the afternoons) that began work on research problems.

  1. Nonnegative matrices and symmetric matrices; graphs and bipartite graphs
  2. Graph eigenvalues
  3. Applications of Rado's Theorem
  4. Colin de Verdiere number $\mu(G)$
  5. Classes of matrices of 0s and 1s
  6. Matrix sign patterns - a peek in two directions
  7. Levy/Desplanques, Taussky, Gershgorin and More
  8. Tournaments
  9. Matrix Polytopes
  10. Digraphs and Eigenvalues of (0,1)-matrices

Research groups
  1. Minimum rank - Hogben - 160 Carver
  2. Inertias - Barrett & Hall - Carver 74
  3. Sign Patterns - Olesky and van de Driessche -  Carver 98
  4. Skew-symmetry - McDonald -  Carver 128 or 305
  5. Tournaments (T^3) - Shader -  Carver 190

Poster Session and Reception

The following students presented posters (list including titles)
Craig Erickson
Colin Garnett
Kathleen Kiernan
Seth Meyer
Reshmi Nair
Travis Peters               
Darren D. Row
Michael Schroeder
John Sinkovic

The Poster Session was well attended.

The Poster Session was preceded by a reception. 

Follow-up activities

For research related to the topics of this conference, consider the BIRS special issue of Linear Algebra and its Applications.

Related special sessions are happening and/or will be proposed at AMS Sectionals:

Minimum rank problems, organized by Lon Mitchel and Sivaram Narayan, November 6-7, 2010 (Saturday - Sunday) University of Richmond, Richmond, VA (2010 Fall Southeastern Section Meeting)

Special sessions will be proposed for October 14-16, 2011 (Friday - Sunday) University of Nebraska-Lincoln, Lincoln, NE (2011 Fall Central Section Meeting)

Remember the AMS 2013 spring sectional at ISU

Rocky Mountain Mathematics Consortium hosts summer schools

There are REUs with topics related to this conference:

ISU Math/stat REU

Wyoming Math REU

Central Michigan Math REU


Welcome dinner

The Department of Mathematics will host the Conference Welcome Dinner at Olde Main Brewing Co. Restaurant, 316 Main Street Ames, IA (515) 232-0553 at 7 PM Sunday July 11.  Participants who have cars should drive themselves and arrive at 7 PM (see map below).  Those who arrive by air will be transported in vans from Frederiksen Court to the restaurant.  The vans will leave at 6:45 PM from the parking lot near the apartments where participants are staying.  Participants who are vegetarian should already have notified the iSU Math Department.

Monday morning

There are several conference participants who have been living in Frederiksen Court for more than a month.  They have volunteered to act as guides Monday morning and will come to the apartments of new arrivals about 7:50 AM to walk with anyone who would like to walk in a group to Carver Hall.  These students will be introduced at the Welcome Dinner. 

WebCT Access

ISU people who are registered for the conference should have been enrolled in the WebCT class and should be able to log in with ISU netID and password.  If you have a problem, e-mail Leslie to verify enrollment only.  Non ISU people who are registered should have been e-mailed a codes to access this WebCT class.  If you did not get this e-mail, e-mail Leslie.  If you need help getting onto WebCT or using it, ask someone else from ISU.
The code for non-ISU people will expire on July 19, so download any material you want to keep.

Computer/print access

Computer lab and printing access for non-ISU people can be arranged through the research group leaders.


The group will have lunch M, T, W, Th in the Mezzanine at Union Drive Marketplace = UDM (get food, then go upstairs).  When you swipe your card to pay for lunch they can tell you how much money you have left.  You can use the card for any meal at UDM, also to pay for food/drink at Freddy Community Center/Hawthorn Market.

Group photo

A group photo will be taken immediately following the end of the first lecture on Tuesday morning (Richard Brualdi's Lecture 3).

Tuesday afternoon

After lunch on Tuesday there will be a brief session in 305 to break into research groups.  Once the research groups have formed, they will go to separate rooms.  If you wish to join an afternoon research group, you should think about which of the problems presented Monday afternoon interest you.  Note that you are selecting an area; other questions may be developed by the group as  research progresses.  You can join at most one of these groups. 

Wednesday evening Poster Session and Reception

Nine graduate students will present posters at 7:00 PM in Carver 202.  The poster session will be preceded by a reception at 6:30 in Carver 400.  Students may set up posters between 6 and 6:30.

Friday schedule

On Friday there will be one research report at 8:30 AM. 
Richard Brualdi's first lecture will start as usual at 9:00.
On Friday afternoon there will be four more research reports from 3 - 5 PM.

We recommend breakfast at Union Drive Marketplace (where we have been having lunch). You can use your meal card if it still has money.  There will NOT be coffee or snacks in 400 Carver before the 8:30 talk. There will be coffee, pop, & snacks at mid-morning break and over the lunch break.

The farewell dinner will be at 5:30 at King Buffet.  Vans for those without cars will leave from Carver at 5:15.  Those with cars should return to their cars and drive to King Buffet, 1311 Buckeye Avenue, Ames, IA.

Ames Aquatic Center (walking distance from Freddy) map


Arrival information

AIR If you are flying, you should fly to Des Moines (DSM).  There will be a welcome dinner that evening at 7 PM, so if possible please plan for your flight to arrive by 4:30.   The conference will run through Friday evening, and everyone has housing through Saturday morning, so you should plan for a Saturday departure.  Departure from Ames for DSM should be 2 hours before flight time.  Shuttle service will be provided by Executive Express for participants who fly.   You should reserve your own shuttle through the on-line reservation system using the following method (this will work only if you are a CBMS registered participant, in which case Executive Express already has your name):
You should reserve your own shuttle through the on-line reservation system using the following method:
1) On the main page, click on the reservation link.
2) At the bottom of the reservation page, enter the group code CBMS. 
3) You will then see the reservation page with a message "Welcome to the ISU Math CBMS" at the top. 
4) Follow the instructions to make your reservation but do not enter a credit card number.  The CBMS group defaults to direct billing to ISU Math but it may still ask for a credit card number, which you should not supply. 
5) Please select Home drop off/pick up, since you will be delivered to the check in point at Maple Willow Larch or to Frederiksen Court (if going to MWL, another van will take you to FC).  The Home drop off should be listed as Maple-Willow-Larch if you arrive in DSM by 7:15 PM and Frederiksen Court if you arrive later.  The pick-up point should be Frederiksen Court if you leave Saturday.
6) If you are arriving very late (after the 10:45 PM shuttle), in the directions/other info section you should indicate when your flight is actually arriving, and Executive Express will try to make arrangements for you.
Note:  Do not worry if you did not follow these directions exactly, we work closely with Executive Express to get everyone where they need to be.

DRIVING Ames is 30 miles north of Des Moines on I-35.  From the south take exit 111B to US 30 West  and drive about 6 miles to the ISU-University Boulevard exit.  Go right (north) on University Boulevard to Lincoln Way about 1.5 miles.  Go left (west) on Lincoln Way about 1/4 mile to first traffic light (Beach Ave) and turn right.  MWL is on your right.  From the north take exit 113 to 13th St..  Turn right (west) and go about 4 miles to Grand Ave.  Gos left (south) on Grand about a mile to Lincoln Way.  Turn right (west) and follow Lincoln way for a mile or so past University Boulevard to Beach Ave as above. First go to Maple-Willow-Larch  Conference Desk as directed above to get your keys/keycard and then proceed through campus to Frederiksen Court. Maps are below.

You should plan to arrive in Ames  by  6 PM.

Ames maps

ISU campus map

Maps showing check-in and housing locations

Departure information

Passengers departing by car should check out at the same place (MWL) they checked in- if no one is at the desk there should be a key drop.

Passengers departing by air  should already have received an e-mail about Executive Express shuttle pick-up.
We recommend checking in and printing your boarding pass the day before departure - see your research group leader or Minnie Catral for print access for boarding passes.
Saturday departures by air:  You will be picked up at Freddy by the EE shuttle. The EE shuttle will stop briefly at MWL for key drop.
Friday afternoon departures by air: 
Bring your luggage to the math office between 8 and 8:30 Friday morning.
Give your key folder (everything except your meal card) to Leslie after the last morning lecture (if you keep your meal card to use at lunch Friday, give your meal card to the math office right after lunch).


Applications are now closed. 

We have provided at least local funding (housing and some food) to most participants and also travel support (within the US) for graduate students and post-docs and some faculty participating in the conference. 

IMA PI members may use IMA/PI funds to support travel of their personnel to this conference (faculty and graduate students at IMA PIs were also welcome to apply through this application process for conference funding).  All participants must have applied and be accepted even if support is not required because space is limited.

Web page maintained by Leslie Hogben
Last Update: July 17, 2010