Lei Shi

Prof. Lei Shi

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
26 April 2019 in Symmetry
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
Hari Mohan SrivastavaHari Mohan Srivastava
Hari Mohan Srivastava
Muhammad ArifMuhammad Arif
Muhammad Arif
SHShehzad Hussain
Shehzad Hussain
HKHassan Khan
Hassan Khan
In the current article, we consider certain subfamilies S e ∗ and C e of univalent functions associated with exponential functions which are symmetric along real axis in the region of open unit disk. For these classes our aim is to find the bounds of Hankel determinant of order three. Further, the estimate of third Hankel determinant for the family S e ∗ in this work improve the bounds which was investigated recently. Moreover, the same bounds have been investigated for 2-fold symmetric and 3-fold symmetric functions.

10 May 2019 in Mathematics
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
IAIzaz Ali
Izaz Ali
Muhammad ArifMuhammad Arif
Muhammad Arif
NCNak Eun Cho
Nak Eun Cho
SHShehzad Hussain
Shehzad Hussain
HKHassan Khan
Hassan Khan
In the present article, we consider certain subfamilies of analytic functions connected with the cardioid domain in the region of the unit disk. The purpose of this article is to investigate the estimates of the third Hankel determinant for these families. Further, the same bounds have been investigated for two-fold and three-fold symmetric functions.

27 July 2019 in Mathematics
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
QKQaiser Khan
Qaiser Khan
Gautam SrivastavaGautam Srivastava
Gautam Srivastava
JLJin-Lin Liu
Jin-Lin Liu
Muhammad ArifMuhammad Arif
Muhammad Arif
Starlike functions have gained popularity both in literature and in usage over the past decade. In this paper, our aim is to examine some useful problems dealing with q-starlike functions. These include the convolution problem, sufficiency criteria, coefficient estimates, and Fekete–Szegö type inequalities for a new subfamily of analytic and multivalent functions associated with circular domain. In addition, we also define and study a Bernardi integral operator in its q-extension for multivalent functions. Furthermore, we will show that the class defined in this paper, along with the obtained results, generalizes many known works available in the literature.

14 April 2022 in Fractal and Fractional
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
MSMeshal Shutaywi
Meshal Shutaywi
NANasser Alreshidi
Nasser Alreshidi
Muhammad ArifMuhammad Arif
Muhammad Arif
SGSyed Muhammad Ghufran
Syed Muhammad Ghufran
The main focus of this research is to solve certain coefficient-related problems for analytic functions that are subordinated to a unique trigonometric function. For the class Ssin*, with the quantity zf′(z)f(z) subordinated to 1+sinz, we obtain an estimate on the initial coefficient a4 and an upper bound of the third Hankel determinant. For functions in the class BTsin, with f′(z) lie in an eight-shaped domain in the right-half plane, we prove that its upper bound of third Hankel determinant is 116. All the results are proven to be sharp.

21 September 2022 in Mathematics
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
Hari Mohan SrivastavaHari Mohan Srivastava
Hari Mohan Srivastava
ARAyesha Rafiq
Ayesha Rafiq
Muhammad ArifMuhammad Arif
Muhammad Arif
MIMuhammad Ihsan
Muhammad Ihsan
In the present paper, we aimed to discuss certain coefficient-related problems for the inverse functions associated with a bounded turning functions class subordinated with the exponential function. We calculated the bounds of some initial coefficients, the Fekete–Szegö-type inequality, and the estimation of Hankel determinants of second and third order. All of these bounds were proven to be sharp.

1 October 2021 in Symmetry
Verified
Journal Article
Open access
PDF file
LSLei Shi
Lei Shi
BABakhtiar Ahmad
Bakhtiar Ahmad
NKNazar Khan
Nazar Khan
MKmuhammad ghaffar khan
muhammad ghaffar khan
Serkan AraciSerkan Araci
Serkan Araci
Bilal KhanBilal Khan
Bilal Khan
By making use of the concept of basic (or q-) calculus, many subclasses of analytic and symmetric q-starlike functions have been defined and studied from different viewpoints and perspectives. In this article, we introduce a new class of meromorphic multivalent close-to-convex functions with the help of a q-differential operator. Furthermore, we investigate some useful properties such as sufficiency criteria, coefficient estimates, distortion theorem, growth theorem, radius of starlikeness, and radius of convexity for this new subclass.