IEEE Computational Intelligence Magazine - February 2020 - 96

University of Southern California, USA.
His citation counts are almost the same
as that of his university.
Castillo from Tijuana Institute of
Technology contributed 90.77% to pub-

lications and 96.26% to citations of that
institute. After University of Southern
California, the highest citations per
paper (ACPP = 105) were found for De
Montfort University for which the main

contributor was John. The next highest
citations per paper were obtained by
Essex University in the UK, where
Hagras was the main contributor.
F. Co-Authorship Study

TABLE 4 Institutional Productivity, TP, Citations TC.
S. NO.

ORGANIZATIONS

UNIVERSITY OF SOUTHERN CALIFORNIA

10,104

5.75

TIJUANA INST TECHNOLOGY

2,886

5.05

UNIVERSITY OF ESSEX

1,820

2.95

AMIRKABIR UNIVERSITY OF TECHNOLOGY

393

2.72

DE MONTFORT UNIVERSITY

3,465

2.56

KING ABDULAZIZ UNIVERSITY

598

2.33

ISLAMIC AZAD UNIVERSITY

240

2.25

ISTANBUL TECHNICAL UNIVERSITY

475

2.10

UNIVERSIDAD AUTONOMA DE BAJA CALIFORNIA

1,085

2.02

NATIONAL CHUNG HSING UNIVERSITY

771

1.79

V. Discussions and Conclusion

SOUTHEAST UNIVERSITY CHINA

641

1.79

UNIVERSITY OF ALBERTA

535

1.79

CHANG GUNG UNIVERSITY

507

1.63

POLISH ACADEMY OF SCIENCES

431

1.63

DEAKIN UNIVERSITY

362

1.55

BOHAI UNIVERSITY

821

1.40

INDIAN INSTITUTE OF TECHNOLOGY SYSTEM

125

1.40

FENG CHIA UNIVERSITY

423

1.32

NATIONAL TAIWAN UNIVERSITY OF SCIENCE TECHNOLOGY

742

1.32

SHIRAZ UNIVERSITY OF TECHNOLOGY

163

1.32

In this study, we have characterized the
field of T2 FSs which has developed
within the parent discipline of FSs. T2
FSs is a relatively new field, having originated only about 43 years ago in the
USA (in 1975). The top 20 highly cited
papers span about 14 years, from 1999 to
2012 indicating the importance of this
period for the discipline. Twelve papers
in this set of 20 are (co-) authored by
Mendel. He has both the highest number of papers and by far the highest citations in the field. Out of the authors
with more than 10 TP, Mendel has the
second highest citations per paper
(~142.16), the highest being ~157.72
cites per paper obtained by John.
Among the top countr ies with
researchers doing research on T2 FSs,
we find China, followed by Iran, USA,
and Taiwan. Papers published by the
researchers in the USA have the highest
total citations. Citations of the publications by Chinese researchers in the
most recent period were the highest.
Although researchers in China have
produced the highest number of publications, there are only two Chinese
institutions contributing to the top 20
list at ranks 11th and 16th with a total
of 3.18% share. This implies that T2 FS
research in China is distributed across a
number of institutions. Taiwan has four
institutions contributing to a total share

FIGURE 5 Co-authorship structure of the field of T2 FSs.

It can be seen from Fig. 5 that the main
actors have their own groups of coauthors as shown using different colors.
Mendel, John, Hagras, Kumbasar,
Bustince and Kaynak appear as the main
characters in the interconnected clusters
seen on the left. On the right is an independent cluster with few connections to
the other cluster, with Castillo and
Mendez as the main characters. The
interconnection between the left and
right nodes represents the connection
between the authors of both sides.

IEEE COMPUTATIONAL INTELLIGENCE MAGAZINE | FEBRUARY 2020

IEEE Computational Intelligence Magazine - February 2020

Table of Contents for the Digital Edition of IEEE Computational Intelligence Magazine - February 2020