Colloquium Calendar

Spring 08

 

The talks will take place in M-201 at 10:45am. There will be coffee and cookies served at 10:30am.

Contact information: Luis F. Gordillo, gordillo@math.uprm.edu

 

  • Jan 24

Eigenvalues of Graphs and Their Applications: Survey and New Results

Xuerong Yong, Department of Mathematical Sciences, UPR-RUM

 

   The topic belongs to the combination of matrix theory, combinatorics,
and spectral graph theory. The eigenvalues of a graph are defined to be
the eigenvalues of its adjacency matrix. Although there has been much work
on exploring the distribution of eigenvalues of graphs and on finding their
applications in the past decades, research into the graphs which have
applications in applied sciences is still in its infancy and there is much
concerning that is still not well-understood.
    In this presentation, starting with an introduction of the framework
and its development, we first summarize and comment the most recent
representatives which show the applications in numerous applied sciences.
We then present our new results about the graphs that have multiple
eigenvalues, etc. One of our motivations is due to an open problem which
recently has been paid much attention.

 

 

  • Jan 31

Un Algoritmo en la Cerradura de Sistemas Sobredeterminados, para el caso de Ecuaciones Conformes Killing

Alfredo Villanueva, Department of Mathematical Sciences, UPR-RUM

 

   La cerradura de sistemas sobredeterminados en el caso de ecuaciones diferenciales
ordinarias es bastante conocido, y consiste en reducir derivadas altas a
derivadas de primer orden mediante la introduccion de nuevas variables. Esto
permite analizar la existencia de soluciones asi como encontrar tecnicas de
solucion.  El caso de sistemas sobredeterminados de ecuaciones diferenciales parciales
ha carecido de un metodo para efectuar la cerradura de manera sistematica.
Nuestro trabajo presenta un algoritmo para la cerradura de ecuaciones
differenciales parciales en variedades Riemanianas.

 

 

  • Feb 4 (Monday, 4:30pm, M-201)

The Group of Unitaries of a C*-algebra

          Claude L. Schochet, Departement of Mathematics, Wayne State University

   

      Click here for the Abstract .

 

Note: Prof. Schochet will give a second talk on Feb 5, 10:30am, M-201, A Case Study in non-commutative topology, specially for students.

Please click here for the Abstract.

   

 

  • Feb 21

     Mathematical Modeling of Infectious Disease and Virus Competition

     Wei Wei, Department of Mathematics, University of Idaho

 

      Click here for the Abstract.

 

 

  • Feb 28

Autonomous Stochastic Resonance Produces Epidemic Oscillations of Fluctuating Size

Priscilla E. Greenwood, Department of Mathematics and Statistics, Arizona State University

 

          Note: Prof. Greenwood is the Distinguished Speaker of SIDIM. She will give the talk entitled Understanding Neuron Firing and Quiescence, at the event, on March 1.    

         

 

  • Mar 27

Epidemiologia teórica: oportunidades y desafíos

     Juan Pablo Aparicio, School of Science and Technology, Universidad Metropolitana

     (ROOM: M-203)

 

 

  • April 10

Modeling of Human Body Fluids

     Megh R. Goyal, General Engineering Department, UPR-RUM

     (ROOM: M-203)

 

 

 

 

 

Seminars

 

Analysis/Geometry  (Tuesdays at 17:00 in M-312)

 

·        March 11

Arzela-Ascoli theory
     Robert Acar, Department of Mathematical Sciences, UPR-RUM

 

·        March 25

     Brouwer and Schauder fixed-point theorems.

     Robert Acar, Department of Mathematical Sciences, UPR-RUM