
In this paper, we discuss standard approaches to the Hyers-Ulam Mittag Leffler problem of fractional derivatives and nonlinear fractional integrals (simply called nonlinear fractional differential equation), namely two Caputo fractional derivatives using a fractional Fourier transform. We prove the basic properties of derivatives including the rules for their properties and the conditions for the equivalence of various definitions. Further, we give a brief basic Hyers-Ulam Mittag Leffler problem method for the solving of linear fractional differential equations using fractional Fourier transform and mention the limits of their usability. In particular, we formulate the theorem describing the structure of the Hyers-Ulam Mittag Leffler problem for linear two-term equations. In particular, we derive the two Caputo fractional derivative step response functions of those generalized systems. Finally, we consider some physical examples, in the particular fractional differential equation and the fractional Fourier transform.
Citation: Anumanthappa Ganesh, Swaminathan Deepa, Dumitru Baleanu, Shyam Sundar Santra, Osama Moaaz, Vediyappan Govindan, Rifaqat Ali. Hyers-Ulam-Mittag-Leffler stability of fractional differential equations with two caputo derivative using fractional fourier transform[J]. AIMS Mathematics, 2022, 7(2): 1791-1810. doi: 10.3934/math.2022103
[1] | Yudhveer Singh, Devendra Kumar, Kanak Modi, Vinod Gill . A new approach to solve Cattaneo-Hristov diffusion model and fractional diffusion equations with Hilfer-Prabhakar derivative. AIMS Mathematics, 2020, 5(2): 843-855. doi: 10.3934/math.2020057 |
[2] | Hadjer Belbali, Maamar Benbachir, Sina Etemad, Choonkil Park, Shahram Rezapour . Existence theory and generalized Mittag-Leffler stability for a nonlinear Caputo-Hadamard FIVP via the Lyapunov method. AIMS Mathematics, 2022, 7(8): 14419-14433. doi: 10.3934/math.2022794 |
[3] | Thabet Abdeljawad, Sabri T. M. Thabet, Imed Kedim, Miguel Vivas-Cortez . On a new structure of multi-term Hilfer fractional impulsive neutral Levin-Nohel integrodifferential system with variable time delay. AIMS Mathematics, 2024, 9(3): 7372-7395. doi: 10.3934/math.2024357 |
[4] | Antonio Di Crescenzo, Alessandra Meoli . On a fractional alternating Poisson process. AIMS Mathematics, 2016, 1(3): 212-224. doi: 10.3934/Math.2016.3.212 |
[5] | Rahat Zarin, Amir Khan, Pushpendra Kumar, Usa Wannasingha Humphries . Fractional-order dynamics of Chagas-HIV epidemic model with different fractional operators. AIMS Mathematics, 2022, 7(10): 18897-18924. doi: 10.3934/math.20221041 |
[6] | Weerawat Sudsutad, Jutarat Kongson, Chatthai Thaiprayoon, Nantapat Jarasthitikulchai, Marisa Kaewsuwan . A generalized Gronwall inequality via $ \psi $-Hilfer proportional fractional operators and its applications to nonlocal Cauchy-type system. AIMS Mathematics, 2024, 9(9): 24443-24479. doi: 10.3934/math.20241191 |
[7] | Mdi Begum Jeelani, Abeer S. Alnahdi, Mohammed A. Almalahi, Mohammed S. Abdo, Hanan A. Wahash, M. A. Abdelkawy . Study of the Atangana-Baleanu-Caputo type fractional system with a generalized Mittag-Leffler kernel. AIMS Mathematics, 2022, 7(2): 2001-2018. doi: 10.3934/math.2022115 |
[8] | Yuehong Zhang, Zhiying Li, Wangdong Jiang, Wei Liu . The stability of anti-periodic solutions for fractional-order inertial BAM neural networks with time-delays. AIMS Mathematics, 2023, 8(3): 6176-6190. doi: 10.3934/math.2023312 |
[9] | Weerawat Sudsutad, Chatthai Thaiprayoon, Aphirak Aphithana, Jutarat Kongson, Weerapan Sae-dan . Qualitative results and numerical approximations of the $ (k, \psi) $-Caputo proportional fractional differential equations and applications to blood alcohol levels model. AIMS Mathematics, 2024, 9(12): 34013-34041. doi: 10.3934/math.20241622 |
[10] | Qun Dai, Shidong Liu . Stability of the mixed Caputo fractional integro-differential equation by means of weighted space method. AIMS Mathematics, 2022, 7(2): 2498-2511. doi: 10.3934/math.2022140 |
In this paper, we discuss standard approaches to the Hyers-Ulam Mittag Leffler problem of fractional derivatives and nonlinear fractional integrals (simply called nonlinear fractional differential equation), namely two Caputo fractional derivatives using a fractional Fourier transform. We prove the basic properties of derivatives including the rules for their properties and the conditions for the equivalence of various definitions. Further, we give a brief basic Hyers-Ulam Mittag Leffler problem method for the solving of linear fractional differential equations using fractional Fourier transform and mention the limits of their usability. In particular, we formulate the theorem describing the structure of the Hyers-Ulam Mittag Leffler problem for linear two-term equations. In particular, we derive the two Caputo fractional derivative step response functions of those generalized systems. Finally, we consider some physical examples, in the particular fractional differential equation and the fractional Fourier transform.
In recent years, the area related to fractional differential and integral equations has received much attention from numerous mathematicians and specialists. The derivatives of fractional order represent physical models of multiple phenomena in different fields such as biology, physics, mechanics, dynamical systems, and so on (see [1-6] and the references therein).
The possibility of fractional calculus was presented in 1695, when the notation dτdtτh(r) was introduced to indicate the derivative of function h(r) in order τ. Specifically, Leibniz composed a letter to L'Hospital in which he posed an enquiry on the derivative of order τ=1,2 which led to the establishment of fractional calculus. Later on, the fractional derivative was presented by Lacroix [7]. Perhaps the most utilized fractional derivatives are Riemann– Liouville (R–L) and Caputo derivatives, which assume an immodest role in fractional order differential equation.
One of the best examination regions in fractional order differential equation, which receives vast considerations by analysts, entails the existence theory of solution. For details concerning the present hypothesis, see [8-12]. Finding an exact solution of fractional order differential equation is exceptionally difficult and the type of exact solution is regularly is important to study an approximate solution with a relatively simple form and examine how close both the approximate and exact solutions are. Overall, we state that a fractional-order differential equation is said to be Hyers-Ulam (H–U) stable if, for every solution of the fractional-order differential equation, there exists an approximate solution of the concerned equation that is close to it.
Ulam [13] formulated the stability of a functional equation, which was solved by Hyers [14] using an additive function defined on the Banach space. This result led Rassias [15] to study and generalize the stability concept, establishing the Hyers-Ulam-Rassias stability. An integral transform (introduced by Fourier) involves a trigonometric form of the Mittag-Leffler function to identify an analytic solution concerning a differential equation of fractional order. The Fourier transforms, Mittag-Leffler function, and fractional trigonometric function constitute an effective tool for analytic expression of the solution of differential equation of non-integer order. Indeed, the Fourier transform has become popular because of recent developments in differential applications. It is also seen as the easiest and most effective way among many other transforms. Luchko [16] defined the fractional Fourier transform (FRFT) of real order τ,0<τ≤1 and discussed its important properties. The application of fractional Fourier transform for undertaking certain types of differential equations of fractional order has also been conducted. Indeed, there are many studies on fractional Fourier transform and its applications in the literature [17-19].
In 2017, Wang et al. [20] discussed the stability of fractional differential equation based on the right-sided Riemann–Liouville fractional derivatives for continuous function space. The fixed point theorem and weighted space method were exploited. In [21], a study on the H–U stability condition was conducted, focusing on an impulsive R-L fractional neutral functional stochastic differential equation with time delays. In [22], the stability criteria of a class of fractional differential equations were investigated, in which the Krasnoselskii fixed point method was employed. Recently, Upadhyay et al. [23] discussed the R–L fractional differential equations using the Hankel transform method. At present, some remarkable results to the stability of fractional differential equations have been reported (see [24-26] and the references therein). In [27,28], the author studied the Hyers-Ulam stability of linear differential equation by using Fourier transform. To the best of our knowledge, there are no results on Hyers-Ulam stability of fractional differential equation by fractional Fourier transform. Some important works related to the recent development in fractional calculus and its applications should be discussed in [29-31].
Motivated by the ongoing research in this field, we examine the Hyers-Ulam stability and generalized Hyers-Ulam stability of fractional order differential equation in this study becomes
(Dτϑh)(r)=G(r), ∀ r∈R, |
and the delay differential equation of fractional order
(Dτϑh)(r−ξ)=G(r), ∀ r∈R, |
where Dτϑ represents R–L fractional derivative, ξ>0,ϑ∈R and 0<τ≤1 with the help of fractional Fourier transform.
In our investigation, we establish the fractional Fourier transform and present it in an integral form. Furthermore, using the convolution concept and properties of fractional Fourier transform, the solution of the stability conditions concerning fractional order differential equation is established. Specifically, we analyze Hyers-Ulam-Rassias stability of the nonlinear fractional order differential equation of the form
(Dτϑh)(r)=G(r,h(r)), ∀ r∈R, |
and use the fixed point theorems for examining the existence and uniqueness of the solution.
The conduct of the analytical solutions of the fractional differential equation represented by the fractional-order derivative operators is the fundamental profession in numerous stability issues. Motivated by the usage of the Mittag-Leffler functions in many spaces of science and designing we present this paper.
The main aim of this paper is to prove the Hyer-Ulam-Mittag-Leffler stability of the following fractional differential equations using the fractional Fourier transform
(cDτ0+y)(c)−λ(cDδ0+y)(c)=h(c), | (1.1) |
and
(cDτ0+y)(c)−λ(cDδ0+y)y(c)−h(c)=F(c), | (1.2) |
where s>0,λ∈R,p−1<τ≤p,q−1<δ≤q,0<δ<τ,p,q∈N≤p, h(c) and h(c) real functions defined on R+, and cDτ0+ is the Caputo fractional derivative of order τ defined by
(cDτ0+)=1Γ(p−τ)∫c0(c−r)p−τ−1y(p)(r)dr. | (1.3) |
We organize this article as follows. The related fundamental properties, lemmas and definitions are presented in section 2. In section 3, Hyers-Ulam-Mittag-Leffler stability of fractional-order linear differential equation and non-linear differential equation is explained. Numerical examples and conclusions are given in section 4.
The Fourier transform is used, for solving partial differential equations. We will need it only in some applications of fractional calculus so we only give the most important formulas. For further facts, we recommend the same books as for the Laplace transform [2].
Let f(x) be a real function of one real variable, such that its Lebesgue integral over the real numbers converges and such that f(x) with its derivative are piecewise continuous. Then the Fourier image of the function f(x), we denote it by ˆf(k)=F{f(x),x,k}.
ˆf(k)=∫∞−∞f(x)e−ikxdx. |
For Fourier images we will use same letters like for the original function with hat and the variable k.
Consider L1(R) as the space related to the complex-valued Lebesgue integrable function on the real line R with norm
‖h‖=∫R|h(r)|dr. |
The definition of a Fourier transform with respect to a function h∈L1(R) is
ˆH(ω)=(Fh(r))(ω)=∫−∞∞h(r)eiωrdr, ∀ ω∈R. |
The form of the associated inverse Fourier transform is
h(r)=(F−1ˆH(ω))(r)=12π∫−∞∞ˆH(ω)e−iωrdω, ∀ r∈R. |
Note that Fourier transform is useful for conversion of a function between the time and frequency domains. It adopts the principle of rotation operation on the time-frequency distribution.
Definition 1. Given parameter τ, we can express the fractional Fourier transform of function h(r) in a one-dimensional case as follows [32]:
ˆH(ω)=(Fαh(r))(ω)=∫−∞∞h(r)Kτ(r,ω)dr, |
where kernel Kτ(r,ω) is
Kτ(r,ω)={Bτei(r2+ω2)cotτ2−irωcosecτ,τ≠nπ,12πe−irω,τ=π2, |
and n is an integer, while
Bτ=(2πisinτ)−12eiτ2=√1−icotτ2π. |
As such, the form of the associated inverse fractional Fourier transform is
h(r)=12π∫−∞∞Kτ(r,τ)ˆH(ω)dω, |
where
Kτ(r,τ)=(2πisinτ)12sinτe−iτ2e−i(r2+ω2)cotτ2+irωcosecτ=B′τe−iτ2e−i(r2+ω2)cotτ2+irωcosecτB′τ=(2πisinτ)12sinτe−iτ2=√2π(1+icotτ). |
Definition 2. The fractional trigonometric function is denoted by
Eτ(ixτ)=cosrτ+isinrτ, |
with
cosrτ=∑k=0∞(−1)kr2τkΓ(1+2τk) and sinrτ=∑k=0∞(−1)kx(2k+1)τΓ(1+τ(2k+1)). |
Luchko et al. [33] introduced a new fractional Fourier transform Fτ of order τ,(0<τ≤1) and its definition is
ˆHτ(ω)=(Fτh)(ω)=∫−∞∞h(r)eτ(ω,r)dr, |
where
eτ(ω,r)={Eτ(−i|ω|1/τr),ω≤0,Eτ(i|ω|1/τr),ω≥0.sign(ω)={−1,ω<0,1,ω≥0. |
As such, the definition of the associated inverse fractional Fourier transform is
h(r)=12πτ∫−∞∞Eτ(−isign(ω)|ω|1/τx)|ω|1τ−1ˆHτ(ω)dω, |
for any r∈R and τ>0. If τ=1, then ˆHτ(ω) and the classical Fourier transform are the same.
Suppose that the space of a function with fast decrease is denoted as S. In other words, the following relation with respect to the space of infinity differentiable functions v(r) on R is satisfied: Given r∈R and n,k∈N∪{0}. If v(r)∈S⊆R, then
‖vk(r)‖≤M|r|n (n,k∈N∪{0}, n>k;|r|→∞). |
Based on V(R), the following relation with respect to a set of functions v∈S is satisfied:
dnvdrn|r=0=0,n=0,1,2,3,.... |
The Lizorkin space is ϕ(R)⊂L1(R) and it is defined as the Fourier pre-image of the space V(R) in the space S of the form
ϕ(R)={h∈S; F(h)∈V(R)}. |
The reason for using the Lizorkin space is its convenience in using the Fourier transform as well as the inverse Fourier transforms with fractional integration and differentiation operators. The properties and associated details of the Lizorkin space have been discussed in many studies (see [34-36]). In our study, we use F to represent the domain of either real R or complex C. According to the definition of Lizorkin space, the orthogonality condition is satisfied by any function h∈(R). That is
∫∞∞rnh(r)dr=0, n=0,1,2,3,.... |
Note that the property of the Fourier transform and its inverse holds for the space ϕ(R). In other words, both transforms are inverse of one another, that is,
F−1Fh=h, h∈ϕ(R). |
Definition 3. The function (h1∗h2)(r)=∫Rh1(r–τ)h2(τ)dτ is denoted as the convolution of both functions of h1 and h2 defined on ϕ(R).
Some properties of fractional Fourier transform that are closely related to the solution in this study are given as follows. Let h,h1 and h2 be functions belonging to ϕ(R). Then
(1) If (Fτh1)(ω)=(Fτh2)(ω), then h1(r)=h2(r),
(2) F(Fτh(x−ξ))(ω)=eτ(ω,ξ)˜H(ω),
(3) Fτ(h1∗h2)(ω)=Fτ((h1)(ω))Fτ((h2)(ω),
(4) F−1τ(h1h2)(r)=F−1τ(h1)(r))∗F−1τ(h2)(r).
Definition 4. [37] The definition of Riemann–Liouville fractional integral of order τ>0 is
(Iτ+h)(r)=1Γ(τ)∫r−∞(r–t)τ−1h(t)dt (Right Riemann–Liouville fractional integral), |
and
(Iτ−h)(r)=1Γ(τ)∫∞r(t–r)τ−1h(t)dt (Left Riemann–Liouville fractional integral), |
where Re(τ)>0, we have Γ(τ)=∫∞0e−uuτ−1du.
Definition 5. [37] The definition of Riemann–Liouville fractional derivative of order τ>0 is
(Dτ+h)(r)=ddr(I1−τ+h)(r) (Right RiemannLiouville fractional derivative),(Dτ–h)(r)=−ddr(I1−τ–h)(r) (Left RiemannLiouville fractional derivative). |
Our current study considers the definition with respect to a fractional derivative operator Dτϑ of h∈ϕ(R), then
(Dτϑh)(r)=(1–ϑ)(Dτ+h)(r)−ϑ(Dτ−h)(r),0<τ≤1,ϑ∈R, |
where Dτ− and Dτ+ denote the left-hand and right-hand Riemann–Liouville fractional derivatives of order τ, in which 0<τ<1.
We will denote the Caputo differ integral by the capital letter with upper-left index CD. The fractional integral is given by the same expression as before, so for α>0, we have
CD−αa=D−αa, |
The difference occurs for fractional derivatives. A non-integer-order derivative is again defined by the help of the fractional integral, but now we first differentiate f(t) in common sense and then go back by fractional integrating up to the required order. This idea leads to the following definition of the Caputo differ integral.
Definition 6. Let a,T,α be real constants (a<T),nc=max(0,−[−α]) and f(t) a function which is integrable on ⟨a,T⟩ in case nc=0 and nc-times differentiable on ⟨a,T⟩ except on a set of measure zero in case nc>0. Then the Caputo differintegral is defined for t∈⟨a,T⟩ by formula:
CD−αaf(t)=Inc−αa(dncf(t)dtnc). |
Remark 1. For α>0,α∉N0, then
CD−αaf(t)=1Γ(nc−α)∫ta(t−τ)nc−α−1fnc(τ)dτ. |
The reason why nc in the definition of the Caputo derivative is different from n introduced in the Riemann-Liouville case is correspondence with integer-order derivatives. We cannot use n even in the Caputo definition because we would get wrong results for the kth derivative of a function with zero (k+1)th derivative. This would be an effect of the paradox that we would need for the kth derivative a (k+1)-times differentiable function.
Clearly, the Caputo derivative can also be written by the help of fractional integrals of the Riemann-Liouville type
CD−αaf(t)=D−(nc−α)a(dncf(t)dtnc). |
The Caputo derivative of order α=nc is equal to the classical nthc derivative.
Definition 7. Suppose that ρ>0,r>p,ρ,r,p∈R. Then
CDτrh(r)={1Γ(p−τ)∫r0h(p)(r)(r−τ)ρ+1−p,p−1<τ<p, p∈N,dpdrph(r), τ=p∈N, |
is called the Caputo fractional differential operator of order τ.
Definition 8. The left and right Caputo fractional derivatives clDτrh(r) and crDτbh(r) of order τ∈R+ are defined by
cLDτah(r)=LDτah(r)−p−1∑k=0hk(a)k!(r−a)k (left Caputo fractional derivatives), |
and
cRDτbh(r)=RDτbh(r)−p−1∑k=0hk(b)k!(b−r)k (right Caputo fractional derivatives), |
respectively, where p=τ+1 for τ∈N0,p=τ for τ. In particular, when 0<τ<1, then cLDτah(r)=LDτa(h(r)−h(a)) and cRDτbh(r)=RDτb(h(r)−h(b)).
Remark 2. The fractional Fourier transform and Caputo derivative are one-to-one functions.
Some properties of fractional Fourier transform that are closely related to the solution in this study are given, as follows
(1) Dϑ∗f(r)=Jℓ−ϑDϑf(r),
(2) limρ→nDϑ∗f(r)=fℓ(r),
(3) Dϑ∗[τf(r)+g(r)]=τDϑ∗f(r)+Dϑ∗g(r),
(4) Dϑ∗Dqf(r)=Dϑ+ϱ∗f(r)≠DqDϑ∗f(r),
(5) {Dϑ∗f(r);s}=sϑF(s)−∑ℓ−1k=0sϑ−k−1f(k)(0),
(6) {Dϑ∗f(r);ϖ=(−iϖ1ρ),
(7) If f(r)=c=constant, then Dϑ∗c=0,c= constant and
Dϑ∗(f(r)g(r))=∞∑k=0(ϑk)(Dϑ−kf(r))g(k)(r)−ℓ−1∑k=0rk−ϑΓ(k+1−ϑ)((f(r)g(r))(k)(0)). |
Theorem 1. Let r>0,τ∈R,p−1<τ<p,p∈N. Then the following relation between the Riemann-Lioville and the Caupto operators holds
Dτ∗h(r)=Dτh(r)−p−1∑k=0rk−τΓ(k+1−τ)h(k)(r). |
Remark 3. For n=1, i.e., 0<τ<1 one more Dτ∗rp=Dτrp.
Definition 9. The Mittag–Leffler function can be defined in terms of a power series as
Eτ(c)=∞∑k=0ckΓ(τk+1), τ>0 (one parameter), | (2.1) |
Eτ,ϱ(c)=∞∑k=0ckΓ(ϱ+τk), τ>0,ϱ>0 (two parameter). | (2.2) |
Definition 10. The fractional differential equation φ(f,y,Dτ1y,Dτ2y,...,Dτny)=0 has Hyer-Ulam stability if for any continuously differentiable function y satisfies the following inequality
|φ(f,y,Dτ1y,Dτ2y,...,Dτny)|<ϵ, ϵ>0, | (2.3) |
then there exist a solution y0 of (2.3) such that
|y(c)−y0(c)|<K(ϵ) and limϵ→0k(ϵ)=0, |
where k is a stability constant.
Remark 4. Let ϱ∈C,R(ϱ)>0,r>0. Then Fρ(rϱ)=Γ(ϱ+1)(−iσ1ρ)ϱ+1.
In this section, we discuss the Hyer-Ulam-Mittag-Leffler stability of fractional-order linear and non-linear differential equations. Furthermore, these corollaries givens some stable results based on the following theorem and lemma.
Theorem 2. Let γ,δ,∈C,R(γ)>0,R(δ)>0,λ∈R. Then
Fα(rγm+δ−1E(m)γ(λrγ))=(−iσ1α)γ−δm![(−iσ1α)γ−λ]m+1. |
Lemma 1. If R(−iσ1α)>0,λ∈C and |λ(−iσ1α)|<1, then
(1) If γ=δ=τ,r=c,m=0, then
Fα(cτ−1Eτ,τ(λxτ))=1[(−iσ1α)τ−λ]. | (3.1) |
(2) If γ=τ,r=c,m=0, then
Fα(cδ−1Eτ,δ(λxτ))=(−iσ1α)τ−δ[(−iσ1α)τ−λ]. | (3.2) |
(3) If γ=τ−δ,r=c,m=0, then
Fα(cτ−1Eτ−δ,τ(λxτ−δ))=1[(−iσ1α)τ−λ(−iσ1α)δ]. | (3.3) |
In this part, we are going to analyse the Hyers-Ulam-Mittag-Leffler stability of the linear fractional differential equation of the form
(cDα0+y)(c)−λ(cDδ0+y)y(c)=h(c), |
by using fractional Fourier transform method.
Theorem 3. Let λ∈R,p−1<τ≤p,p∈N and let h(c) be a real valued function defined on R. If a function y:(0,∞)→R satisfies
|(cDα0+y)(c)−λ(cDδ0+y)y(c)−h(c)|≤ϵ,ϵ>0, ∀ x>0, | (3.4) |
then there exists a solution ya:(0,∞)→R of (cDα0+y)(c)−λ(cDδ0+y)y(c)=h(c) such that
|y−ya|≤ϵcτEτ,τ+1(|λ|cτ−δ). | (3.5) |
Proof. Putting y(k)(0)=bk, for k=0,1,2,...,p−1 and
y(c)=(cDα0+y)(c)−λ(cDδ0+y)y(c)−h(c). |
Now,
y(c)=[Dτy(c)−p−1∑k=0ck−τΓ(k+1−τ)yk(0)]−λ[Dτy(c)−p−1∑k=0ck−δΓ(k+1−τ)yk(0)]−h(c). |
Taking fractional Fourier transform on both sides, we have
Fα[Y(c)]=Fα[Dτy(c)]−p−1∑k=0bkΓ(k+1−τ)Fα[ck−τ]−λ[Fα[Dτy(c)]p−1∑k=0bkΓ(k+1−δ)Fα[ck−δ]]−Fα[h(c)]=[(−iσ1α)τ−λ(−iσ1α)δ]Fα[y(c)]−Fα[h(c)]−p−1∑k=0bk(−iσ1α)τ−k−1+λp−1∑k=0bk(−iσ1α)δ−k−1, | (3.6) |
Which implies that
[(−iσ1α)τ−λ(−iσ1α)δ]Fα[y(c)]=Fα[Y(c)]−Fα[h(c)]+p−1∑k=0bk(−iσ1α)τ−k−1−λp−1∑k=0bk(−iσ1α)δ−k−1Fα[y(c)]=Fα[Y(c)]−Fα[h(c)][(−iσ1α)τ−λ(−iσ1α)δ]+p−1∑k=0bk(−iσ1α)τ−k−1[(−iσ1α)τ−λ(−iσ1α)δ]+λp−1∑k=0bk(−iσ1α)τ−k−1[(−iσ1α)τ−λ(−iσ1α)δ]. | (3.7) |
Setting
y0(c)=p−1∑k=0bkyk(c)+q−1∑k=nbkyk(c)+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]h(r)dr, | (3.8) |
where yk(c)=ckEτ−δ,k+1(λcτ−δ)−λcτ−δ+kEτ−δ,τ−δ+k+1(λcτ−δ),k=0,1,2,...,q−1,
yk(c)=ckEτ−δ,k+1(λcτ−δ),k=q,...,p−1,
and
y0(c)=q−1∑k=nbkyk(c)+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]h(r)dr. |
Taking fractional Fourier transform on both sides, we have
Fα[ya(c)]=p−1∑k=0bkFα[ckEτ−δ,k+1(λcτ−δ)−λcτ−δ+kEτ−δ,τ−δ+K+1(λcτ+δ)]+p−1∑k=0bkFα[ckEτ−δ,k+1(λcτ−δ)]+Fα[∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]]Fα[h(r)]dr. |
Consequently,
Fα[ya(c)]=[p−1∑k=0bk(−iσ1α)τ−k−1−λp−1∑k=0bk(−iσ1α)δ−k−1+Fα(h(c))](−iσ1α)τ−λ(−iσ1α)δ. | (3.9) |
By (3.7) and a simple computation, we get
(cDα0+ya)(c)−λ(cDδ0+ya)ya(c)=[Dτya(c)−p−1∑k=0ck−τΓ(k+1−τ)y(k)(0)]−λ[Dδya(c)−p−1∑k=0ck−δΓ(k+1−δ)y(k)(0)]Fα[(cDα0+ya)(c)−λ(cDδ0+ya)(c)]=(−iσ1α)τFα[ya(c)]p−1∑k=0bk(−iσ1α)τ−k−1 −λ((−iσ1α)τFα[ya(c)])+λp−1∑k=0bk(−iσ1α)δ−k−1=Fα[h(c)]. | (3.10) |
Since Fα is 1-1, it follows that
(cDα0+ya)(c)−λy(c)=h(c). |
So y0(c) is a solution of (3.4). By (3.7) and (3.9), we get
Fα(y(c)−ya(c))=Fα(y(c))−Fα(ya(c))=Fα(Y(c))(−iσ1α)τ−λ(−iσ1α)δ. | (3.11) |
Using the convolution property, we obtain
Fα(cτ−1Eτ−δ,α(λcτ−δ)∗Y(c))=Fα(cτ−1Eτ−δ,τ(λcτ−δ))Fα(Y(c))=Fα(Y(c))(−iσ1α)τ−λ(−iσ1α)δ. | (3.12) |
By (3.11) and (3.12), we have
y(c)−ya(c)=(cτ−1Eτ−δ,τ(λcα−δ))∗Y(c). | (3.13) |
Therefore, from (3.3) it follows that
|y(c)−ya(c)|=|(cτ−1Eτ−δ,τ(λcα−δ))∗Y(c)|=|∫c0(c−r)τ−1Eτ−δ,τ(λ(c−r)τ−δ)Y(r)dr|=ϵcτEτ−δ,τ+1(|λ|cτ−δ). | (3.14) |
Then by definition of Hyers-Ulam stability, (3.3) has the Hyers-Ulam stability.
Corollary 1. Let λ∈R,p−1<τ≤p,p∈N and let h(c) be a real valued function defined on R, also χ(c)∈R. If y0:(0,∞)→R satisfies
|(cDτ0+y)(c)−λ(cDδ0+)y(c)−h(c)|≤χ(c)ϵ, ϵ>0, ∀ x>0, | (3.15) |
then there exists a solution y0:(0,∞)→R of
(cDτ0+y)(c)−λ(cDδ0+)y(c)=h(c), |
such that
|y−y0|≤ϵχ(c)cτEτ−δ,τ+1(|λ|cτ). | (3.16) |
In this section, we are going to analyse the Hyers-Ulam-Mittag-Leffler stability of the non-Linear fractional differential equation of the form
(cDα0+y)(c)−λ(cDδ0+)y(c)−h(c)=F(c), |
by using the fractional Fourier transform method.
Theorem 4. Let λ∈R,p−1<τ≤p,p∈N and let h(c) be a real valued function defined on R. If a function y:(0,∞)→R satisfies
|(cDα0+y)(c)−λ(cDδ0+)y(c)−h(c)|≤F(c),ϵ>0, ∀ x>0, | (3.17) |
then there exists a solution ya:(0,∞)→R of
(cDα0+y)(c)−λ(cDδ0+)y(c)−h(c)=F(c), |
such that
|y−ya|≤C(c), here C(c)=cτEτ−δ,τ+1(|λ|cτ−δ). | (3.18) |
Proof. Putting y(k)(0)=bk, for k=0,1,2,...,p−1 and
y(c)=(cDα0+y)(c)−λ(cDδ0+)y(c)−h(c)−F(c),y(c)=[Dτy(c)−p−1∑k=0ck−τΓ(k+1−τ)yk(0)]−λ[Dδy(c)−p−1∑k=0ck−δΓ(k+1−δ)yk(0)]−h(c)−F(c). |
Taking fractional Fourier transform on both sides, we have
Fα[y(c)]=Fα[Dτy(c)]−p−1∑k=0bkΓ(k+1−τ)Fα[ck−τ]−λ[Fα[Dτy(c)]−p−1∑k=0bkΓ(k+1−τ)Fα[ck−τ]]−Fα[h(c)]−Fα[F(c)] | (3.19) |
=(−iσ1α)τFα[y(c)]−p−1∑k=0bkΓ(k+1−τ)(−iσ1α)τ−k−1Γ(k+1−τ)−λ[(−iσ1α)τFα[y(c)]−p−1∑k=0bkΓ(k+1−τ)(−iσ1α)τ−k−1Γ(k+1−τ)]−Fα[h(c)]. | (3.20) |
That is,
[(−iσ1α)τ−λ(−iσ1α)δ]Fα[y(c)]=p−1∑k=0bk(−iσ1α)τ−k−1−λp−1∑k=0bk(−iσ1α)δ−k−1+Fα[Y(c)]+Fα[h(c)]+Fα[F(c)],Fα[y(c)]=p−1∑k=0bk(−iσ1α)τ−k−1[(−iσ1α)τ−λ(−iσ1α)δ]−λp−1∑k=0bk(−iσ1α)δ−k−1[(−iσ1α)τ−λ(−iσ1α)δ]+Fα[Y(c)]+Fα[h(c)]+Fα[F(c)][(−iσ1α)τ−λ(−iσ1α)δ]. | (3.21) |
Setting
y0(c)=q−1∑k=0bkyk(c)p−1∑k=mbkyk(c)+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]h(r)dr+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]F(r)dr, | (3.22) |
where yk(c)=ckEτ−δ,K+1(λcτ−δ)−λcτ−δ+kEτ−δ,τ−δ+k+1(λcτ−δ),k=0,1,2,...,q−1,
yk(c)=ckEτ−δ,K+1(λcτ−δ),k=q,...,p−1,
and
ya(c)=p−1∑k=1bkyk(c)+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]h(r)dr+∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]F(r)dr. |
Taking fractional Fourier transform on both sides, we have
Fα[ya(c)]=q−1∑k=1bkFα[ckEτ−δ,k+1(λcτ−δ)−λcτ−δ+kEτ−δ,τ−δ+k+1(λcτ+δ)]+p−1∑k=mbkFα[ckEτ−δ,k+1(λcτ−δ)]+Fα[∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]]Fα[h(r)]dr+Fα[∫c0(c−r)τ−1Eτ−δ,τ[λ(c−r)τ−δ]]Fα[F(r)]dr. |
That is,
Fα[ya(c)]=[p−1∑k=0bk(−iσ1α)τ−k−1−λp−1∑k=0bk(−iσ1α)δ−k−1+Fα(h(c))++Fα(F(c))](−iσ1α)τ−λ(−iσ1α)δ. | (3.23) |
By (3.7) and a simple computation, we get
(cDα0+ya)(c)−λ(cDδ0+ya)(c)−h(c)=[Dτy0(c)−p−1∑k=0ck−τΓ(k+1−τ)y(k)a(0)]−λ[Dδya(c)−p−1∑k=0ck−δΓ(k+1−δ)y(k)a(0)]−h(c), |
Fα[(cDα0+ya)(c)−λ(cDδ0+ya)(c)]=(−iσ1α)τFα[ya(c)]p−1∑k=0bk(−iσ1α)τ−k−1 −λ((−iσ1α)τFα[ya(c)])+λp−1∑k=0bk(−iσ1α)δ−k−1−Fα[h(c)]=Fα[h(c)]. | (3.24) |
Since Fα is 1-1, it follows that
(cDα0+ya)(c)−λy(c)=h(c). |
So ya(c) is a solution of (3.4). By (3.7) and (3.9), we get
Fα(y(c)−y0(c))=Fα(y(c))−Fα(ya(c))=Fα(Y(c))(−iσ1α)τ−λ(−iσ1α)δ. | (3.25) |
Using the convolution property, we can get
Fα(cτ−1Eτ−δ,α(λcτ−δ)∗Y(c))=Fα(cτ−1Eτ−δ,τ(λcτ−δ))Fα(Y(c))=Fα(Y(c))(−iσ1α)τ−λ(−iσ1α)δ. | (3.26) |
By (3.11) and (3.12), we have
y(c)−ya(c)=(cτ−1Eα,α+1(λcα−δ))∗Y(c). | (3.27) |
Therefore, from (3.3) it follows that
|y(c)−ya(c)|=|(cτ−1Eτ−δ,τ(λcα−δ))∗Y(c)|=|∫c0(c−r)τ−1Eτ−δ,τ(λ(c−r)τ−δ)Y(r)dr|=F(c)cτEτ−δ,τ+1(|λ|cτ−δ). | (3.28) |
Then by definition of Hyers-Ulam-Mittag-Leffler stability, the fractional differential Eq (1.2) has the Hyers-Ulam stability.
Corollary 2. Let λ∈R,p−1<τ≤p,p∈N and let h(c) be a real valued function defined on R, also χ(c)∈R. If ya:(0,∞)→R satisfies the inequality
|(cDτ0+y)(c)−λ(cDδ0+y)y(c)−h(c)−h(c)|≤χ(c)ϵ,ϵ>0, ∀ x>0, | (3.29) |
then there exists a solution y0:(0,∞)→R of
(cDτ0+y)(c)−λ(cDδ0+y)y(c)−h(c)=h(c), |
such that |y−y0|≤C(c), here
C(c)=χ(c)h(c)cτEτ−δ,τ+1(|λ|cτ−δ). | (3.30) |
We consider the fractional differential equation
rDα1/2u(r,s)=tDβu(r,s),r∈R,s∈R+, |
where the α,β are real parameters always restricted as follows 0<α≤1,0<β≤2, rDα1/2=12(rDα+−rDα−) is the space-fractional derivative of order α and sDβ∗ is the Caputo time-fractional derivative of order β(m−1<β≤m,m∈N) defined as follows:
rDβ∗h(s)={Γ(m−β)∫s0f(m)(τ)(s−τ)β+1−mdτ,m−1<β<m,dmdsmh(s),β=m. |
This operator has been referred to as the Caputo fractional derivative since it was introduced by Caputo in the late 1960's for modeling the energy dissipation in some anelastic materials with it is well known that for a sufficiently well-behaved function h the property
L{sDβ∗h(t);t}=tβ˜h(t)−m−1∑k=0tβ−1−kh(k)(0+),m−1<β≤m, |
holds true, L being the Laplace transform
˜h(t)=L{h(s);t}=∫∞oe−tsh(t)dt, R(t)>ah, |
of a function h. A sufficient condition of the existence of the Laplace transform is that the original function is of exponential order as t→∞. This means that some constant ah exists such that the product e−ahs|h(s)| is bounded for all t greater than some T. Then ˜h(t) exists and is analytic in the half plane R(t)>ah.
In this part, some examples are given to illustrate linear fractional differential equation and non linear fractional differential equation for use our main theoretical part.
Example 1. Let the linear fractional differential equation
(cD120+y)(c)−13(cD130+y)(c)=23c32−35c53Γ(53), | (5.1) |
where τ=12,λ=13,δ=13,h(c)=23c32−35c53Γ(53).
For ϵ=12, it is very easy to check that the function y1(c)=c2 satisfies
|(cD120+y)(c)−13(cD130+y)(c)−23c32+35c53Γ(53)|<12, |
and initial values of y1(c) are y1(0)=y′1=0. From (3.8) and the initial values of y1(c), we get an exact solution of Eq (5.1)
y0(c)=∫c0(c−r)−12E1612(13(c−r)16)(23r32−35c53Γ(53))dr. |
By theorem 3.3, the control function of y1(c) is 12c12E16,32(13c12), thus
|y1(c)−y0(c)|<12c12E16,32(13c12), |
Using MATLAB, the solution of (5.1) is computed and depicted in Figure 1. In addition, the error of the approximate solution y1(c) can be estimated.
Example 2. Let the non-linear fractional differential equation
(cD20+y)(c)−13(cD520+y)(c)=52−23√π√c, | (5.2) |
where τ=12,δ=52,λ=13,h(c)=52−23√π√c.
For ϵ=12, it is very easy to check that the function y1(c)=c2 satisfies
|(cD20+y)(c)−13(cD520+y)(c)−52+23√π√c|<12, |
and initial values of y1(c) and y1(0) are 0. From (3.25) and the initial values of y1(c), we get an exact solution of Eq (5.2)
y0(c)=∫c0(c−r)−12E11212(13(c−r)−12)(52−23√π√c)dr. |
By theorem 3.3, the control function of y1(c) is 12c2E112,3(13c12), thus
|y1(c)−y0(c)|<12c2E112,3(13c12). |
Using MATLAB, the solution of (5.2) is computed and depicted in Figure 2. An error of the approximate solution y1(c) can be estimated.
This paper may be divided into three main parts, the framework of Hyers-Ulam Mittag Leffler problem of fractional derivatives and nonlinear fractional integrals, namely two Caputo fractional derivatives using a fractional Fourier transform. the fractional calculus, the theory of linear fractional differential equations and examples of the fractional calculus. In the beginning, we recalled some techniques, classes of functions and basic integral transforms which are necessary for further investigation of the fractional calculus rules. Then we introduced some standard approaches to the definition of fractional differential equations, namely the Riemann-Liouville and the two Caputo fractional approaches and the sequential fractional derivative, and studied their basic properties. In particular, we formulate the theorem describing the structure of the Hyers-Ulam Mittag Leffler problem for linear two-term equations. In particular, we derive the two Caputo fractional derivative step response functions of those generalized systems. We gave some examples of the fractional differential equation for important functions like the power function and functions of the Mittag-Leffler type. Finally, we considered the fractional differential equation of a discontinuous function where some of their effects were demonstrated.
The authors extend their appreciation for the Deanship of Scientific Research at King Khalid University for funding through the research group program under grant number R.G.P2/39/42.
The authors declare that they have no competing interests.
[1] |
E. Bazhlekova, I. Bazhlekov, Viscoelastic flows with fractional derivative models: Computational approach by convolutional calculus of Dimovski, Fract. Calc. Appl. Anal., 17 (2014), 954–976. doi: 10.2478/s13540-014-0209-x. doi: 10.2478/s13540-014-0209-x
![]() |
[2] | I. Podlubny, Fractional differential equations: An introduction to fractional derivatives, fractional differential equations, methods of their solution and some of their applications, Elsevier, 1998. |
[3] |
J. T. Machado, V. Kiryakova, F. Mainardi, Recent history of fractional calculus, Commun. Nonlinear Sci., 16 (2011), 1140–1153. doi: 10.1016/j.cnsns.2010.05.027. doi: 10.1016/j.cnsns.2010.05.027
![]() |
[4] |
F. Liu, K. Burrage, Novel techniques in parameter estimation for fractional dynamical models arising from biological systems, Comput. Math. Appl., 62 (2011), 822–833. doi: 10.1016/j.camwa.2011.03.002. doi: 10.1016/j.camwa.2011.03.002
![]() |
[5] |
D. Baleanu, A. Jajarmi, H. Mohammadi, S. Rezapour, A new study on the mathematical modelling of human liver with Caputo-Fabrizio fractional derivative, Chaos Soliton. Fract., 134 (2020), 109705. doi: 10.1016/j.chaos.2020.109705. doi: 10.1016/j.chaos.2020.109705
![]() |
[6] |
D. Baleanu, S. Etemad, S. Rezapour, A hybrid Caputo fractional modeling for thermostat with hybrid boundary value conditions, Bound. Value Probl., 2020 (2020), 64. doi: 10.1186/s13661-020-01361-0. doi: 10.1186/s13661-020-01361-0
![]() |
[7] | S. F. Lacroix, Traité du cacul différential et du calcul intégral, Paris: Courcier, 1819. |
[8] |
A. Ali, B. Samet, K. Shah, R. A. Khan, Existence and stability of the solution to a toppled system of differential equations of non-integer order, Bound. Value Probl., 2017 (2017), 16. doi: 10.1186/s13661-017-0749-1. doi: 10.1186/s13661-017-0749-1
![]() |
[9] |
K. Shah, W. Hussain, Investigating a class of nonlinear fractional differential equations and its Hyers-Ulam stability by means of topological degree theory, Numer. Func. Anal. Opt., 40 (2019), 1355–1372. doi: 10.1080/01630563.2019.1604545. doi: 10.1080/01630563.2019.1604545
![]() |
[10] |
D. Baleanu, A. Mousalou, S. Rezapour, On the existence of solutions for some infinite coefficient-symmetric Caputo-Fabrizio fractional integrodifferential equations, Bound. Value Probl., 2017 (2017), 145. doi: 10.1186/s13661-017-0867-9. doi: 10.1186/s13661-017-0867-9
![]() |
[11] |
D. Baleanu, R. P. Agarwal, H. Mohammadi, S. Rezapour, Some existence results for a nonlinear fractional differential equation on partially ordered Banach spaces, Bound. Value Probl., 2013 (2013), 112. doi: 10.1186/1687-2770-2013-112. doi: 10.1186/1687-2770-2013-112
![]() |
[12] |
D. Baleanu, S. Rezapour, H. Mohammadi, Some existence results on nonlinear fractional differential equations, Philos. Trans. R. Soc. A, Math. Phys. Eng. Sci., 371 (2013), 20120144. doi: 10.1098/rsta.2012.0144. doi: 10.1098/rsta.2012.0144
![]() |
[13] | S. M. Ulam, A collection of mathematical problems, Interscience Publishers, 1960. |
[14] |
D. H. Hyers, On the stability of the linear functional equation, P. Natl. Acad. Sci. USA., 27 (1941), 222–224. doi: 10.1073/pnas.27.4.222. doi: 10.1073/pnas.27.4.222
![]() |
[15] |
T. M. Rassias, On the stability of the linear mapping in Banach spaces, P. Am. Math. Soc., 72 (1978), 297–300. doi: 10.2307/2042795. doi: 10.2307/2042795
![]() |
[16] | Y. Luchko, M. M. Yuri, Some new properties and applications of a fractional Fourier transform, J. Inequal. Spec. Funct., 8 (2017), 13–27. |
[17] | H. M. Ozaktas, M. A. Kutay, The fractional Fourier transform, In: 2001 European Control Conference (ECC), 2001, 1477–1483. doi: 10.23919/ECC.2001.7076127. |
[18] |
K. Liu, J. Wang, Y. Zhou, D. O'Regan, Hyers-Ulam stability and existence of solutions for fractional differential equations with Mittag-Leffler kernel, Chaos Soliton. Fract., 132 (2020), 109534. doi: 10.1016/j.chaos.2019.109534. doi: 10.1016/j.chaos.2019.109534
![]() |
[19] |
H. Vu, T. V. An, N. V. Hoa, Ulam-Hyers stability of uncertain functional differential equation in a fuzzy setting with Caputo-Hadamard fractional derivative concept, J. Intell. Fuzzy Syst., 38 (2020), 2245–2259. doi: 10.3233/JIFS-191025. doi: 10.3233/JIFS-191025
![]() |
[20] |
C. Wang, T. Z. Xu, Stability of the nonlinear fractional differential equations with the right-sided Riemann-Liouville fractional derivative, Discrete Cont. Dyn. S, 10 (2017), 505–521. doi: 10.3934/dcdss.2017025. doi: 10.3934/dcdss.2017025
![]() |
[21] |
Y. Guo, X. B. Shu, Y, Li, F. Xu, The existence and Hyers-Ulam stability of solution for an impulsive Riemann-Liouville fractional neutral functional stochastic differential equation with an infinite delay of order 1<β<2, Bound. Value Probl., 2019 (2019), 59. doi: 10.1186/s13661-019-1172-6. doi: 10.1186/s13661-019-1172-6
![]() |
[22] |
Q. Dai, R. Gao, Z. Li, C. Wang, Stability of Ulam-Hyers and Ulam-Hyers-Rassias for a class of fractional differential equations, Adv. Differ. Equ., 2020 (2020), 103. doi: 10.1186/s13662-020-02558-4. doi: 10.1186/s13662-020-02558-4
![]() |
[23] | S. K. Upadhyay, K. Khatterwani, Characterizations of certain Hankel transform involving Riemann-Liouville fractional derivatives, Comp. Appl. Math., 38 (2019), 24. doi: doi.org/10.1007/s40314-019-0791-y. |
[24] |
D. Baleanu, S. Rezapour, Z. Saberpour, On fractional integrodifferential inclusions via the extended fractional Caputo-Fabrizio derivation, Bound. Value Probl., 2019 (2019), 79. doi: 10.1186/s13661-019-1194-0. doi: 10.1186/s13661-019-1194-0
![]() |
[25] |
M. S. Aydogan, D. Baleanu, A. Mousalou, S. Rezapour, On high order fractional integrodifferential equations including the Caputo-Fabrizio derivative, Bound. Value Probl., 2018 (2018), 90. doi: 10.1186/s13661-018-1008-9. doi: 10.1186/s13661-018-1008-9
![]() |
[26] |
A. Khan, M. T. Syam, A. Zada, H. Khan, Stability analysis of nonlinear fractional differential equations with Caputo and Riemann–Liouville derivatives, Eur. Phys. J. Plus, 133 (2018), 264. doi: 10.1140/epjp/i2018-12119-6. doi: 10.1140/epjp/i2018-12119-6
![]() |
[27] |
A. Mohanapriya, A. Ganesh, N. Gunasekaran, The Fourier transform approach to Hyers-Ulam stability of differential equation of second order, J. Phys. Conf. Ser., 1597 (2020), 012027. doi: 10.1088/1742-6596/1597/1/012027. doi: 10.1088/1742-6596/1597/1/012027
![]() |
[28] |
A. Mohanapriya, C. Park, A. Ganesh, V. Govindan, Mittag-Leffler-Hyers-Ulam stability of differential equation using Fourier transform, Adv. Differ. Equ., 2020 (2020), 389. doi: 10.1186/s13662-020-02854-z. doi: 10.1186/s13662-020-02854-z
![]() |
[29] |
D. Baleanu, S. S. Sajjadi, A. Jajarmi. Z. Defterli, On a nonlinear dynamical system with both chaotic and nonchaotic behaviors: A new fractional analysis and control, Adv. Differ. Equ., 2021 (2021), 234. doi: 10.1186/s13662-021-03393-x. doi: 10.1186/s13662-021-03393-x
![]() |
[30] |
D. Baleanu, S. S. Sajjadi, H. Jihad, A. Jajarmi, E. Estiri, Hyperchaotic behaviors, optimal control, and synchronization of a nonautonomous cardiac conduction system, Adv. Differ. Equ., 2021 (2021), 157. doi: 10.1186/s13662-021-03320-0. doi: 10.1186/s13662-021-03320-0
![]() |
[31] |
D. Baleanu, S. Zibaei, M. Namjoo, A. Jajarmi, A nonstandard finite difference scheme for the modeling and nonidentical synchronization of a novel fractional chaotic system, Adv. Differ. Equ., 2021 (2021), 308. doi: 10.1186/s13662-021-03454-1. doi: 10.1186/s13662-021-03454-1
![]() |
[32] |
A. I. Zayed, Fractional Fourier transform of generalized functions, Integral Transform. Spec. Funct., 7 (1998), 299–312. doi: 10.1080/10652469808819206. doi: 10.1080/10652469808819206
![]() |
[33] | Y. F. Luchko, H. Matrínez, J. J. Trujillo, Fractional Fourier transform and some of its applications, Fract. Calc. Appl. Anal., 11 (2008), 457–470. |
[34] | P. I. Lizorkin, Liouville differentiation and the functional spaces Lpr(En). Imbedding theorems, Mat. Sb. (N. S.), 60 (1963), 325–353. |
[35] |
P. I. Lizorkin, Generalized Liouville differentiation and the method of multipliers in the theory of embeddings of function classes, Math. Notes Acad. Sci. USSR, 4 (1968), 771–779. doi: 10.1007/BF01093718. doi: 10.1007/BF01093718
![]() |
[36] | S. Samko, Denseness of the spaces ΦV of Lizorkin type in the mixed L¯p(Rn)-spaces, Stud. Math., 113 (1995), 199–210. |
[37] |
A. A. Kilbas, J. J. Trujillo, Differential equations of fractional order: Methods, results and problems-I, Appl. Anal., 78 (2001), 153–192. doi: 10.1080/00036810108840931. doi: 10.1080/00036810108840931
![]() |
1. | Ahmed Salem, Sanaa Abdullah, Non-Instantaneous Impulsive BVPs Involving Generalized Liouville–Caputo Derivative, 2022, 10, 2227-7390, 291, 10.3390/math10030291 | |
2. | Zain Ul Abadin Zafar, Nigar Ali, Mustafa Inc, Zahir Shah, Samina Younas, Mathematical modeling of corona virus (COVID-19) and stability analysis, 2022, 1025-5842, 1, 10.1080/10255842.2022.2109020 | |
3. | Arunachalam Selvam, Sriramulu Sabarinathan, Samad Noeiaghdam, Vediyappan Govindan, Yusuf Gurefe, Fractional Fourier Transform and Ulam Stability of Fractional Differential Equation with Fractional Caputo-Type Derivative, 2022, 2022, 2314-8888, 1, 10.1155/2022/3777566 | |
4. | Muath Awadalla, Mohamed Hannabou, Kinda Abuasbeh, Khalid Hilal, A Novel Implementation of Dhage’s Fixed Point Theorem to Nonlinear Sequential Hybrid Fractional Differential Equation, 2023, 7, 2504-3110, 144, 10.3390/fractalfract7020144 | |
5. | Yannan Sun, Wenchao Qian, Fast algorithms for nonuniform Chirp-Fourier transform, 2024, 9, 2473-6988, 18968, 10.3934/math.2024923 | |
6. | M. R. Lemnaouar, Existence and k‐Mittag–Leffler–Ulam stabilities of a Volterra integro‐differential equation via (k,ϱ)‐Hilfer fractional derivative, 2024, 0170-4214, 10.1002/mma.10572 | |
7. | Wen-Hua Huang, Muhammad Samraiz, Ahsan Mehmood, Dumitru Baleanu, Gauhar Rahman, Saima Naheed, Modified Atangana-Baleanu fractional operators involving generalized Mittag-Leffler function, 2023, 75, 11100168, 639, 10.1016/j.aej.2023.05.037 | |
8. | Sina Etemad, Ivanka Stamova, Sotiris K. Ntouyas, Jessada Tariboon, Quantum Laplace Transforms for the Ulam–Hyers Stability of Certain q-Difference Equations of the Caputo-like Type, 2024, 8, 2504-3110, 443, 10.3390/fractalfract8080443 | |
9. | Yamin Sayyari, Mehdi Dehghanian, Choonkil Park, Some stabilities of system of differential equations using Laplace transform, 2023, 69, 1598-5865, 3113, 10.1007/s12190-023-01872-w | |
10. | Tahir Ullah Khan, Christine Markarian, Claude Fachkha, Stability analysis of new generalized mean-square stochastic fractional differential equations and their applications in technology, 2023, 8, 2473-6988, 27840, 10.3934/math.20231424 | |
11. | Mei Wang, Baogua Jia, Finite-time stability and uniqueness theorem of solutions of nabla fractional $ (q, h) $-difference equations with non-Lipschitz and nonlinear conditions, 2024, 9, 2473-6988, 15132, 10.3934/math.2024734 |