VISIT:

 

 

GERAD and HEC Montreal, Montreal QC, Canada (27.01.2017--26.02.2017). .

 

Department of Mathematics, Mongolian National University of Education, Ulaanbaatar, Mongolia (21.08.2016--28.08.2016).

 

Center of Combinatorics, Nankai University, Tianjin, China (09.07.2016--14.07.2016).

 

Department of Mathematics, Shanghai University, Shanghai, China (01.07.2016--01.07.2016).

 

Department of Mathematics, East China University of Science and Technology, Shanghai, China (28.06.2016--03.07.2016).

 

Kragujevac University, Kragujevac, Serbia (21.05.2016--25.05.2016).

 

Universidade Federal do Rio de Janeiro, Brazil (18.02.2016--29.02.2016).

 

Instituto de Matemtica, UFRGS Avenida Bento Gonalves, Porto Alegre, RS, Brazil (11.02.2016--18.02.2016).

 

Department of Mathematics, Delaware University, Delaware, USA (01.02.2016--10.02.2016).

 

Department of Mathematics, University of Kashan, Kashan, Iran (22.08.2015--24.08.2015).

 

Department of Mathematics, Shahid Rajaee, Teacher Training University, Tehran, Iran (19.08.2015--22.08.2015).

 

Department of Mathematics, Universiti of Putra Malaysia, Kuala Lumpur, Malaysia (24.06.2015--30.06.2015).

 

Department of Mathematics, South China normal University, Guangzhou, China (12.01.2015--12.01.2015).

 

Department of Mathematics, South China Agricultural University, Guangzhou, China (11.01.2015--18.01.2015).

 

Department of Mathematics, Shanghai University, Shanghai, China (08.01.2015--08.01.2015).

 

Department of Mathematics, East China University of Science and Technology, Shanghai, China (04.01.2015--11.01.2015).

 

Department of Mathematics, Yantai University, Yantai, China (27.12.2014--04.01.2015).

 

Dept. of Mathematics, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (23.12.2014--27.12.2014,~18.01.2015--22.01.2015).

 

Department of Mathematics, Beijing Institute of Technology, Beijing, China (28.11.2014--01.12.2014).

 

Dept. of Mathematics, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (28.05.2014--01.06.2014).

 

Dept. of mathematics, Uludag University, Bursa, Turkey (16.08.2013--25.08.2013).

 

Vijayanagara Sri Krishnadevaraya University, Bellary, India (23.02.2013--25.02.2013).

 

Dept. of Mathematics, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (17.01.2013--05.02.2013).

 

Dept. of mathematics, Uludag University, Bursa, Turkey (22.08.2012--31.08.2012).

 

Dept. of mathematics, Selcuk University, Konya, Turkey (13.08.2012--21.08.2012).

 

Indian Statistical Institute, Kolkata, India (18.01.2011--30.01.2011).

 

The Institute of Mathematical Sciences (IMSc), Chennai, India, (22.01.2008--01.02.2008).

 

Indian Statistical Institute, New Delhi, India (18.02.2007--24.02.2007).

Conference Talk/Invited Talk:

 

 

On energy, Laplacian energy and signless Laplacian energy of graphs, 12th Annual Meeting of the IAMC \& 2016 ICMC, Nankai University, Tianjin, China (04.07.2016--08.07.2016). .

 

On (Signless) Laplacian eigenvalues of graphs, Spectra of graphs and applications 2016, May 1820, 2016, Serbian Academy of Sciences and Arts, Belgrade, Serbia (18.05.2016--20.05.2016). .

 

On Laplacian eigenvalues of graphs, 46th Annual Iranian Mathematics Conference (AIMC 46), Yazd University, Yazd, Iran (24.08.2015---29.08.2015). .

 

Proof of conjectures on the distance signless Laplacian eigenvalues of graphs, Renmin University, Beijing, China (28.11.2014---30.11.2014) (The First International Conference on Big Data \& Applied Stat.) .

 

On Kirchhoff index, Laplacian energy and Laplacian-energy-like invariant of graphs, KSIAM, Jeju, South Korea (20.11.2014--23.11.2014). .

 

Relation between energy of different matrices from graph, Shanghai Jio-Tang University, Shanghai, China (24.05.2014---28.05.2014) (The Eight Shanghai Conference on Combinatorics May 24th May 28, 2014 Shanghai). .

 

Eigenvalues of graph matrices and graph parameters, Moscow State University, Moscow, Russia (26.01.2014---02.02.2014) (Moscow Workshop on Combinatorics and Number Theory). .

 

Relation between eigenvalues of the graph matrices and the graph parameters, Tohuku University, Sendai, Japan (28.11.2013---01.12.2013). .

 

Sharp bounds on the energy of graphs, Balikesir University, Balikesir,Turkey (12.08.2013---15.08.2013). .

 

Eigenvalues and graph parameters, NCAAM, Reva Institute of Technology and Management, Bangalore, India (22.02.2013). .

 

The number of spanning trees of a graph, Bursa Conference, Bursa, Turkey (23.08.2012). .

 

On conjectures involving second largest signless Laplacian eigenvalue of graphs, KMS-AMS meeting, Seoul, Korea, December 2009. .

 

Bounds on the degree distance of a graph, Combinatorics workshop, Sungkyunkwan Unibversity, Suwon, South Korea, August 2008. .

 

On the conjecture for certain Laplacian integral spectrum of graphs, International Conference on Linear Algebra, Shanghai University, Shanghai, China, July 2007. .

 

Laplacian Spectrum of a Graph, Workshop on Graph Theory and Combinatorics in Ballarat University, Ballarat, Australia, October 2004. .

TALK:

 

 

On Laplacian eigenvalues of graph, GERAD and HEC Montreal, Montreal, QC, Canada (09.02.2017). .

 

On Laplacian eigenvalues of graph, Department of Mathematics, Mongolian National University of Education, Ulaanbaatar, Mongolia (25.08.2016). .

 

On the Laplacian spread of a graph, Shanghai University, Shanghai, China (01.07.2016). .

 

On Laplacian eigenvalues of graphs, University of Kragujevac, Kragujevac, Serbia (24.05.2016). .

 

Energy and Laplacian energy of graphs, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil (24.02.2016). .

 

On Laplacian eigenvalues of graphs, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil (22.02.2016). .

 

On (signless) Laplacian eigenvalues of graphs, Department of Mathematics, Delaware University, Delaware, USA (08.02.2016). .

 

Spectral graph theory: Four common spectra, Department of Chemistry, Korea University, Seoul, Republic of Korea (04.12.2015). .

 

On (signless) Laplacian eigenvalues of graphs, Department of Mathematics, Shahid Rajaee, Teacher Training University, Tehran, Iran (22.08.2015). .

 

Comparison between topological indices of graphs, Institut Penyelidikan Matematik, Universiti Putra Malaysia Kualalumpur, Kualalumpur, Malaysia (30.06.2015). .

 

Comparison between the Szeged index and the eccentric connectivity index, South China Agricultural University, Guangzhou, China (13.01.2015). .

 

On the distance signless Laplacian eigenvalues of graphs, South China normal University, Guangzhou, China (12.01.2015). .

 

On Laplacian eigenvalues of graphs, Shanghai University, Shanghai, China (08.01.2015). .

 

Proof of conjectures on the distance signless Laplacian eigenvalues of graphs, East China University of Science and Technology, Shanghai, China (05.01.2015). .

 

On Kirchhoff Index and degree Kirchhoff index of graphs, Yantai University, Yantai, China (31.12.2014). .

 

Comparison between the Szeged index and the eccentric connectivity index, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (25.12.2014). .

 

On Kirchhoff Index of graphs, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (29.05.2014). .

 

Eigenvalues and Energy of He matrix of the Hexagonal Systems, Vijayanagara Sri Krishnadevaraya University, Bellary, India (25.02.2013). .

 

On algebraic connectivity of graphs, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (19.01.2013). .

 

The relation between eigenvalues of graphs with graph parameters, Nanjing University of Aeronautics \& Astronautics, Nanjing, China (18.01.2013). .

 

Graph, Eigenvalues and Applications, Selcuk University, Konya, Turkey (16.08.2012). .

 

The Institute of Mathematical Sciences (IMSc), Chennai, India, January, 2008. .

 

Hannam University, Taejon, South Korea, March 2007. .

 

Sungkyunkwan University, South Korea, December 2006. .

 

LRI, University Paris-XI, Paris, France, December 2005. .

 

Pohang University of Science and Technology, Pohang, South Korea, April 2005. .

 

Ballarat University, Australia, November 2004. .

Last Updated on :30 August,2004