
INTERNATIONAL LINEAR ALGEBRA SOCIETY (ILAS), Member, 2000 to 2015, (International)

Persatuan Matematik Malaysia (PERSAMA), Life Member, 2009, (National)

Acta Mathematica Sinica, English Series, Article Reviewer, 2011 to 2011, (International)

The Malaysian Journal of Science, Editorial Board Member, 2011 to 2014, (University)

AMERICIAN MATHEMATICAL SOCIETY (AMS), Member, 2014 to 2015, (International)

LINEAR AND MULTILINEAR ALGEBRA (LAMA)  REVIEWER, Article Reviewer, 2015 to 2015, (International)
ADMINISTRATIVE DUTIES
(Role), (Level), (Start date),(End Date).

Auditor Dalaman ISM, Faculty, 01/09/2018 to 01/09/2019

Jawatankuasa Ijazah Tinggi ISM, Faculty, 01/09/2018 to 01/09/2019

Internal Auditor for "Audit Kendiri Fakulti Sains 2018", Faculty, 21/05/2018 to 25/05/2018 (Internal Auditor for "Audit Kendiri Fakulti Sains 2018" appointed by Dean of Faculty of Science Professor Dr. Zanaria Abdullah for conducting the audit in PT01: Teaching and Learning Aspect.)

Scientific Committee Member of the 4th International Statistical Conference 2018 (ISMIV), National, 25/04/2018 to 03/08/2018 (4th International Statistical Conference 2018 (ISMIV), Sunway University and Institute Statistics Malaysia, August 12, 2018. Sunway University, Malaysia)

Jawatankuasa Ijazah Tinggi ISM, Faculty, 01/09/2017 to 01/09/2018

Auditor Dalaman ISM, Faculty, 01/09/2017 to 01/09/2018

Internal Auditor for 18/2017, University Malaya, 13/02/2017 to 01/06/2017 (The internal audit had been conducted from 25 April 2017  19 May 2017 for Bil18/2017. However, the appointment and preparation task force started in Feb 2017.)

Deputy Head, Faculty, 01/09/2016 to 13/08/2017 (I am conducting 5 month sabbatical leave staring from 14 August 2017.)

Coordinator of the Higher Degree for ISM, Faculty, 01/09/2016 to 13/08/2017 (I am conducting 5 month sabbatical leave starting fron 14 August 2017. )

Library Representative for ISM , Faculty, 01/09/2016 to 13/08/2017 (I am conducting sabbatical leave from 14 August 2917  13 January 2018 )

LIBRARY REPRESENTATIVE FOR THE INSTITUTE OF MATHEMATICAL SCIENCES, FACULTY OF SCIENCE, Faculty, 02/12/2014 to 01/06/2016

Jawatankuasa Spesifikasi dan Penilaian Teknikal, University Malaya, 18/11/2011 to 01/03/2012

Quality Manager, Faculty, 02/09/2010 to 31/12/2012

The Chairman of Seminar Committee of the Institute of Mathematical Sciences, Faculty of Science, Institute of Mathematical Sciences, Faculty of Science, 01/05/2009 to 30/09/2010

Internal Auditor of UM, University Malaya, 01/05/2008 to 01/12/2012

Library Representative for the Institute of Mathematical Sciences, Faculty of Science., Faculty, 01/01/2008 to 01/12/2014
AREAS OF EXPERTISE
(Area).

Linear and Multilinear Algebra (Matrix Theory, Linear Algebra, Multilinear Algebra, Tensor Spaces, Geometry of Matrices, Kronecker Product of Matrices, Functional Identity)
RECENT SELECTED PUBLICATIONS
(Publication).
Chapter in Book
2006

W.L. Chooi (2006), Complex numbers and elementary
functions,
Engineering Mathematics I, 2nd Edition, 237
286. Pearson Prentice Hall (ISBN:9789833655151).

W.L. Chooi (2006), Calclulus of one variable,
Engineering Mathematics I, 2nd Edition, 1220.
Pearson Prentice Hall (ISBN:9789833655151)

W.L. Chooi (2006), Complex Variables, Engineering
Mathematics II, 2nd
Edition, 385652,
Pearson Prentice Hall (ISBN:9789833655168).
Article in Academic Journals
2018

Chooi, W. L., & Kwa, K. H. (2018). Classical adjoint commuting and determinant preserving linear maps on Kronecker products of Hermitian matrices. Linear and Multilinear Algebra, (ISIIndexed)

Chooi, W. L., & Kwa, K. H. (2018). Additive maps of rank r tensors and symmetric tensors. Linear and Multilinear Algebra. (ISIIndexed)

Chooi, W. L., Kwa, K. H., & Tan, L. Y. (2018). Commuting maps on rank k triangular matrices. Linear and Multilinear Algebra. (ISIIndexed)
2017

Chooi, W. L., Kwa, K. H., & Lim, M. H. (2017). Coherence invariant maps on tensor products. Linear Algebra and its Applications, 516, 2446. (ISIIndexed)
2016

Chooi, W. L., Kwa, K. H., & Lau, J. ( 2016). A note on classical adjoint commuting linear maps of tensor products of matrices. Linear and Multilinear Algebra, 64(4), 745766. (ISIIndexed)
2014

Chooi, W.L., & Ng, W.S. (2014). Classical adjoint commuting mappings on alternate matrices and skewHermitian matrices. Operators and Matrices, 8(2), 485512. (ISIIndexed)

Chooi, W. L., Kwa, K. H., Lim, M. H., & Ng, Z. C. (2014). Linear spaces and preservers of bounded ranktwo persymmetric triangular matrices. Electronic Journal of Linear Algebra, 27, 619651. (ISIIndexed)
2013

Chooi, W.L., Lim, M.H., & Ng, Z.C. (2013). Linear spaces and preservers of symmetric matrices of bounded ranktwo. Linear and Multilinear Algebra, 61(8), 10511062. (ISIIndexed)
2011

Chooi, W.L. & Ng, W.S. (2011). Classical adjointcommuting mappings on Hermitian and symmetric matrices. Linear Algebra and its Applications, 435, 202223. (ISIIndexed)

Chooi, W.L. (2011), Compoundcommuting additive maps. J. Korean Math. Soc., 48(1), 83104. (ISIIndexed)
2010

Chooi, W.L. (2010). Rankone nonincreasing additive maps between block triangular matrix algebras. Linear and
Multilinear Algebra, 58(6), 715740. (ISIIndexed)

Chooi, W.L., & Ng, W.S. (2010). On classical adjointcommuting mappings between matrix algebras. Linear Algebra and its
Applications, 432, 25892599. (ISIIndexed)
2006

Chooi, W .L., & Lim, M. H. (2006), Additive rankone preservers on block triangular matrix spaces. Linear Algebra and its Applications, 416(23), 588607. (ISIIndexed)
2005

Chooi, W.L., & Lim, M.H. (2005), Additive preservers of rankadditivity on matrix spaces. Linear Algebra and
its Applications, 402(1), 291302. (ISIIndexed)
2004

Chooi, W.L., & Lim, M.H. Lim (2004). Additive preservers of rankadditivity on matrix spaces. Journal of Natural Science of Heilongjiang University, 21(4), 4649. (NonISI/NonSCOPUS)
2003

Chooi, W.L., & Lim, M.H. (2003), Some linear preserver problems on block triangular matrix algebras. Linear Algebra and its Applications, 370(1), 2539. (ISIIndexed)

Chooi, W.L., Lim, M.H., & Semrl, P. (2003). Adjacency preserving maps on upper triangular matrix algebras. Linear Algebra and its Applications, 367(1), 105130. (ISIIndexed)
2002

Chooi, W. L., & Lim, M. H. (2002), Coherence invariant mappings on block triangular matrix spaces. Linear Algebra and its Applications, 346(13), 199238. (ISIIndexed)

Chooi, W. L., & Lim, M. H. (2002), Rankone nonincreasing mappings on triangular matrices and some related preserver problems. Linear and Multilinear Algebra, 49(4), 305336. (ISIIndexed)
1998

Chooi, W.L., & Lim, M.H. (1998), Linear preservers on triangular matrices. Linear Algebra and its Applications, 269(13), 241255. (ISIIndexed)
Proceeding
2002

W.L. Chooi and M.H. Lim (2002), Rankone
nonincreasing
linear maps on block triangular matrix algebras,
Proceeding of 10th National Mathematical Sciences
Symposium, 7278, Johor Baharu, Malaysia.
1996

W.L. Chooi and M.H. Lim (1996), Product preserving
linear transformations on matrix spaces, Proceeding
of
the 7th National Mathematical Sciences Symposium, 312
318, Kuala Lumpur, Malaysia.
Extended Abstract
2009

W.L. Chooi (2009), Compoundcommuting additive maps
between square matrix,
5th IMTGT International Conference on Mathematics,
Statistics and their Applications (ICMSA) 2009, June
9
11, 2009, West Sumatera, Indonesia.
2008

W.L. Chooi (2008), Rankone nonincreasing additive
maps between block
triangular matrix algebars,
8th International Conference on Matrix Theory and
its
Applications (ICMTA 2008), July 1618, 2008, Taiyuan
Normal University, China.

W.L. Chooi (2008), Adjugatecommuting additive maps
on
triangular matrices over an arbitrary field, One Day
Seminar in Mathematics UM 2008, July 1, 2008,
Institute of Mathematical Sciences, University of
Malaya.
2007

W.L. Chooi (2007), Additive rankone preservers on
triangular matrices,
Invited talk,
3rd International Mathematics and Physical Sciences
Graduate Congress 2007 (MPSGC 2007), December 1214,
2007, University of Malaya, Malaysia.

W.L. Chooi and M.H. Lim (2007), Additive mappings
preserving rankadditivity on block
triangular matrix algebras,
3rd IMTGT Regional Conference on Mathematics,
Statistics and Applications (IMTGTRCMSA 2007),
December 56, 2007, Penang, Malaysia.
2001

W.L. Chooi and M.H. Lim (2001), Coherence invariant
mappings on block triangular matrices, the 9th
International Linear Algebra Society Conference, June
2529, 2001, Institute of Advanced Studies in
Mathematics, TechnionIsrael Institute of Technology,
Haifa, Israel.
2000

W.L. Chooi (2000), Compoundcommuting linear mappings
on matrices, The 7th SIAM Conference on Applied
Linear Algebra, October 23 ¿C 26, 2000, Jane S.
McKimmon Conference Center, North Carolina State
University, Raleigh, North Carolina.
1999

W.L. Chooi (1999), Adjugatecommuting maps on
triangular matrices, The 8th International Linear
Algebra Society Conference, July 1922, 1999.
Escola Tecnica Superior d¿¿Enginyers Industrials,
ETSEIBUPC, Barcelona, Spain.
AREAS OF RESEARCH
(Project title), (Role), (From)(Until), (Level), (Source).

PRESERVER PROBLEMS ON TENSOR PRODUCTS RELATED TO QUANTUM INFORMATION SCIENCE, Principal Investigator(PI), 2019  2020, Fundamental Research Grant Scheme (FRGS), (National)

Preserver Problems on Tensor Products related to Quantum Information Sciences, Principal Investigator(PI), 2018  2020, Fundamental Research Grant Scheme (FRGS), (International)

Some Presever Problems On Tensor Products Related To Functional Idendities, Principal Investigator(PI), 2018  2020, RU Geran  Fakulti Program, (National)

Some Preserver Problems on Tensor Products related to Functional Identities, Principal Investigator(PI), 2018  2020, University Malaya Faculty Research Grant , (National)

Preserver Problems On Tensor Product Of Matrices Related To Quantum Information Science., Principal Investigator(PI), 2014  2017, Geran Penyelidikan Universiti Malaya (UMRG)  AFR (Frontier Science), (University)

Geometry Of Triangular Matrices And Its Applications In Preserver Problems, Principal Investigator(PI), 2013  2015, Fundamental Research Grant Scheme (FRGS), (National)

Nonlinear Preserver Problems on Matrix and Tensor
Spaces, Principal Investigator(PI), 2011  2014, Geran Penyelidikan Universiti Malaya (UMRG), (National)

GENERAL CLASSICAL ADJOINTCOMMUTING MAPPINGS ON MATRIX SPACES, , 2009  2010, Postgraduate Research Grant (PPP)  Research, (National)

Additive Preserver Problems on Matrix Spaces and
its Applications, Principal Investigator(PI), 2008  2011, Fundamental Research Grant Scheme (FRGS), (National)

Operators on matrices with invariance of lie
products, Principal Investigator(PI), 2008  2009, Short Term Research Fund (Vote F)(PJP), (National)

Some Studies on Preserver Problems on Triangular
Matrices, Principal Investigator(PI), 2007  2008, Short Term Research Fund (Vote F)(PJP), (University)

Preserver Problems on Spaces of Matrices or
Operators and their Applications, Principal Investigator(PI), 2007  2009, ScienceFund, (National)

SOME STUDIES ON PRESEVER PROBLEMS ON TRIANGULAR MATRICES, Principal Investigator(PI), 2007  2008, RU Geran, (National)

Linear preserver problems on spaces of matrices
or operators, Principal Investigator(PI), 2002  2004, IRPA (MOSTI), (National)
CONSULTATION PROJECT/CONSULTANCY
(Project title), (Role), (From)(Until), (Organisation).

Editor of Malaysian Journal of Science, 20112011, Malaysian Journal of Science

Reviewer, 20112011, Acta Sinica Mathematical (English Series), Springer

Reviewer, 20112011, Linear and Multilinear Algebra

Internal Auditor, 20102010, QMEC, University of Malaya
AWARDS AND RECOGNITIONS
(Name of Award), (Awarding Institution), (Year Awarded), (Level).

Adjunct Associate Professor in School of Mathematical Sciences, Sunway University, Malaysia, Sunway University, Malaysia, 2018, (National)

Excellence Service Award, University Malaya, 2015, (University)

Seoul Icm2014 Nanum 2014 Travel Grants Award, The International Congress of Mathematician 2014, 2014, (International)

Ambassador of The 2014 International Congress of Mathematicians Icm2014, The International Congress of Mathematicians 2014, 2013, (International)

Excellence Service Award, University Malaya, 2012, (University)

Certificate of Excellent Service, University Malaya, 2011, (University)

Sijil Perkhidmatan Cemerlang 2010, University of Malaya, 2011, (University)
PRESENTATIONS
(Title), (Event), (Date Presented), (Organiser), (Level).
PRESENTER
 Product preserving linear transformations on matrix
spaces, The 7th National Mathematical Sciences Symposium, 19961203 to 19961205, (National)
 Geometry of triangular matrices, Centro de Estruturas Lineares e Combinotorias CLEC Seminorio, Complexo Interdisciplinar, June 17 2002, University of Lisboa, Portugal.
, 20020617 to 20020617, University of Lisboa, Portugal.
, (University)
 Rankone nonincreasing linear maps on block triangular
matrix algebras, The 10th National Mathematical Sciences Symposium, 20041223 to 20041224, (National)
 Rankone preserving additive mappings on triangular matrices, International Workshop on Preserver Problems, May 5 7 2005, University of Hong Kong, Hong Kong. , 20050505 to 20050507, University of Hong Kong, (International)
 On classical ajoint commuting mapping between matrix algebras, The 16th Conference of the International Linear Algebra Society, 20100621 to 20100625, Internatioal Linear Algebra Society, University of Pisa, (International)
 Additive maps of rank r tensors, Workshop on Matrix Theory and Graph Theory, 20170124 to 20170124, Institute of Mathematical Sciences, (International)
INVITED SPEAKER
 Additive mapping persevering rankadditivity on matrix spaces
, Invited Speaker, The 6th International Conference on Matrix Theory and its Applications 2004.
, 20040701 to 20040704, (International)
 Additive rankone preservers on triangular matrices, Invited Speaker, The 3rd Mathematics and Physical Sciences International Graduates Congress, 20071212 to 20071214, University of Malaya., (International)
 Classical adjoint commuting mappings on Hermitian and symmetric matrices, The Fifth Workshop on Matrices and Operators, 20100711 to 20100715, Shanxi Association for Science and Technology, Taiyuan University of Technology and Shanxi Normal University, (International)
 Some studies on the geometry of block triangular matrices, The 6th International Workshop on Matrices and Operators (MAO2011), 20110708 to 20110711, College of William and Mary (USA) and University of Electronic Science and Technology of China (China), (International)
PLEANARY/KEYNOTE SPEAKER
 Linear Preserver Problems and their Recent Developments, The 11th IMTGT International Conference on Mathematics, Statistics and its Applications 2015, ICMSA2015, 20151123 to 20151125, King Mongkut's Institute of Technology Ladkrabang, (International)
EVENT ORGANISER
 A characterization of surjective classical adjoint commuting maps on matrix algebras, Seminar in Mathematical Sciences 2009, 20091030 to 20091101, Insitute of Mathematical Sciences, University of Malaya, (National)
ORAL
 Bounded distance preserving surjective mappings on triangular matrices, International Conference on Rings and Algebas, 20110710 to 20110716, Kent State University (USA), National Taiwan University (Taiwan) and National Cheng Kung University (Taiwan), (International)
 A note on adjoint preserving mappings on complex Hermitian and skewHermitian matrices, Simposium Kebangsaan Sains dan Matematik ke19, 20111109 to 20111111, Jabatan Sains Komputer dan Matematik, UiTM Pulau Pinang, (National)
EVALUATION ACTIVITIES
(Description), (Evaluation Activity),(Year).

As a review panel to review the proceeding papers submitted to the 4th ISM International Statistical Conference 2018 (ISMIV) for the consideration of publication., Article In Proceeding ,
(2018  2018)

As a scholar in linear and multilinear algebra, we are invited to review manuscripts (related to linear algebra and matrix theory) submitted to Malaysian Journal of Science for publication., Article In Journal ,
(2006  2010)

As a scholar in linear and multilinear algebra, we will be invited to review manuscript submitted to Linear Multilinear Algebra for a possible publication., Article In Journal ,
(2001  2017)

As a scholar in linear and multilinear algebra, we will be invited to review manuscript submitted to Linear Algebra and its Applications for a possible publication., Article In Journal ,
(2000  2014)
CONTRIBUTION TO SOCIETY
(Contribution To Society), (Level), (Start Date), (End Date).

Ambassador of the 2014 International Congress of Mathematicians (ICM2014) and its Invitition Program NANUM2014, (International), 01/01/2013 until 01/08/2014
POST GRADUATE STUDENT
(Name of Degree), (Name of Candidates), (Title of Thesis), (Academic Session)
Completed

Master Degree, Lau Jin Ting (sgp130010), Some Linear Preserver Problems on Tensor Products of Matrices, 2013/2014

Master Degree, Ng Zhen Chuan (sgp100007), Linear spaces and preservers of persymmetric triangular matrices of bounded ranktwo, 2011/2012

Doctoral Degree (phd), Ng Wei Shean (shb 080010), GENERALISED CLASSICAL ADJOINTCOMMUTING MAPPINGS ON MATRIX SPACES, 2008/2009
Ongoing

Doctoral Degree (phd), Tan Li Yin, Additive Maps of Selected Subsets of Matrices, 2017/2018