Research interests: Graph theory, Combinatorial matrix theory

 Publications:

1. The Erdos-Jacobson-Lehel conjecture on potentialy P k -graphic  sequences is true, Sci. China Ser. A 41 (1998), no. 5, 510--520(With Jiongsheng Li and Zixia Song) .

2. An extremal problem on potentially 3C l-graphic sequences, J. Math. Study  31 (1998), no. 4, 362--369(with Jiongsheng Li and Yunkai Liu).

3.  Potentially 3C l- graphic sequences. J. Univ. Sci. Technol. China 29 (1999), no. 1, 1-- 8 (With Jiongsheng Li) .

 4. Upper Bound for the Non-maximal Eigenvalues of Irreducible Nonnegative Matrices, Czechoslovak Math. J. 52(127) (2002), no. 3, 537—544 (With Xiaodong Zhang).

 5. Potentially C k-graphic sequences,  Ars Combinatoria, 64(2002), 31.

 6. The Spectral Radius of Triangle-free Graphs, Australas. J. Combin. 26 (2002), 33--39 (with Xiaodong Zhang).

 7. Edge Coloring of Embedded Graphs with Large Girth, Graphs and Combinatorics,  19 (2003), no. 3, 393 – 401 (with Xuechao Li).

 8. The Laplacian Eigenvalues of Mixed Graphs, Linear Algebra and its applications., 362(2003) 109-119 (with Xiaodong Zhang).   

 9. Edge-face chromatic number and edge-chromatic number (with C. Q. Zhang), to appear in Journal of Graph Theory.

 10. Nowhere-zero 4-flows, simultaneous edge-colorings, and critical partial Latin squares (with  Wenan Zang, C.Q. Zhang), to appear in  Combinatorica.

11. Kp- minors in p-connected graphs (with K Kawarabayashi, J Niu and C. Q Zhang), to appear in European J. Com.

 12. Edge-coloring of simple graphs with small average degrees,  Discrete Math. 275(2004), 207-218 (with C. Q. Zhang).

 13. On potentially Kk -graphic sequences (with Morgan Warner), accepted by Ars Combinatoria on Feb 2, 2003. 

 14. A note on class one graphs  with maximum degree six (with X. Li), Submitted

 

   

Presentations

 1.On Potentially P-graphic sequences, Combinatorics Seminar, Feb 12, 1999, Department of Mathematics, West Virginia University

  2. Edge-face chromatic number and edge-chromatic number, The Ninth Quadrennial International Conference on Graph Theory, Combinatorics, Algorithms and Applications, June 14—20, Western Michigan University

  3. On the Edge-face coloring of plane graphs, the 22nd Midwest Graph Theory Conference, Oct. 13-14, 2000, Wright State University.

  4. Total chromatic number of graphs with small genus, Combinatorics Seminar, Sept. 23, 2000, West Virginia University

  5. Edge-coloring and edge-face coloring of simple planar graphs, Conference on Horizons in Combinatorics, May 21-24, 2001, Vanderbilt University

 6. The  Laplacian Eigenvalues of Mixed Graphs,  AMS Southeastern Section Meeting, Chattanooga, TN, October 5-6, 2001, University of Tennessee, Chattanooga

7.. Some Results on Perfect Graphs, Combinatorics Seminar,  Aug. 29, Sept. 5, Sept. 19, 2001, West Virginia University

8. Edge coloring of simple graphs with small maximum degree, Seminar in graph theory and combinatorics, Mar. 17, 2003, Vanderbilt University

9. Edge coloring of simple graphs with small maximum degree, Colloquium, Mar. 19, 2003, Department of Mathematical Sciences, Middle Tennessee State University 

10.  Edge coloring of simple graphs with small maximum degrees, the 37th Midwestern Graph Theory Conference, Sept 19-20, 2003, Valparaiso University

11. Edge coloring of simple graphs with small maximum degree, Colloquium, Mar. 19, 2003, Department of Mathematical Sciences, Middle Tennessee State University

12.  Edge coloring of simple graphs with small maximum degrees, the 37th Midwestern Graph Theory Conference, Sept 19-20, 2003, Valparaiso University

13.  Edge colorings of graphs, Research seminar of the college of basic and applied sciences, October 15, 2003

14.  Random Graphs, Graph Theory Seminar, Department of Mathematical Sciences, January 26, 2004.

15. Coloring edges of graphs embedded in a surface of Euler characteristic –3, CombinaTexas 04, April 9-10, 2004, Texas A&M University

 

 

Invited Talks

1.      Nowhere-zero 4-flows, simultaneous edge-coloring,   Discrete Math Seminar, Dec. 4, 2001, University of Illinois at Urbana-Champain  

2.      Flows and colorings, Dec 19, 2001, University of Science and Technology of China  

3.      Edge-face coloring of simple plane graphs, Dec. 24, 2001, Shanghai Jiaotong University  

4.      Edge colorings of graphs with small average degree, AMS meeting in Orlando, November  9-10.

5.  On the degree sequences of simple graphs,  Integers conference 2003, State University of West Georgia, GA, Oct. 31-Nov 2, 2003

 

Grants

Refereed papers for