\documentclass[reqno]{amsart} \usepackage{hyperref} \AtBeginDocument{{\noindent\small \emph{Electronic Journal of Differential Equations}, Vol. 2013 (2013), No. 81, pp. 1--21.\newline ISSN: 1072-6691. URL: http://ejde.math.txstate.edu or http://ejde.math.unt.edu \newline ftp ejde.math.txstate.edu} \thanks{\copyright 2013 Texas State University - San Marcos.} \vspace{9mm}} \begin{document} \title[\hfilneg EJDE-2013/81\hfil Existence of solutions] {Existence of solutions to impulsive fractional partial neutral stochastic integro-differential inclusions with state-dependent delay} \author[Z. Yan, H. Zhang\hfil EJDE-2013/81\hfilneg] {Zuomao Yan, Hongwu Zhang} % in alphabetical order \address{Zuomao Yan \newline Department of Mathematics, Hexi University, Zhangye, Gansu 734000, China} \email{yanzuomao@163.com} \address{Hongwu Zhang \newline Department of Mathematics, Hexi University, Zhangye, Gansu 734000, China} \email{zh-hongwu@163.com} \thanks{Submitted September 25, 2012. Published March 29, 2013.} \subjclass[2000]{34A37, 60H10, 34K50, 34G25, 26A33} \keywords{Impulsive stochastic integro-differential inclusions; \hfill\break\indent state-dependent delay; multi-valued map; fractional neutral integro-differential inclusions} \begin{abstract} We study the existence of mild solutions for a class of impulsive fractional partial neutral stochastic integro-differential inclusions with state-dependent delay. We assume that the undelayed part generates a solution operator and transform it into an integral equation. Sufficient conditions for the existence of solutions are derived by using the nonlinear alternative of Leray-Schauder type for multivalued maps due to O'Regan and properties of the solution operator. An example is given to illustrate the theory. \end{abstract} \maketitle \numberwithin{equation}{section} \newtheorem{theorem}{Theorem}[section] \newtheorem{lemma}[theorem]{Lemma} \newtheorem{definition}[theorem]{Definition} \newtheorem{remark}[theorem]{Remark} \allowdisplaybreaks \section{Introduction} The study of impulsive functional differential or integro-differential systems is linked to their utility in simulating processes and phenomena subject to short-time perturbations during their evolution. The perturbations are performed discretely and their duration is negligible in comparison with the total duration of the processes and phenomena. Now impulsive partial neutral functional differential or integro-differential systems have become an important object of investigation in recent years stimulated by their numerous applications to problems arising in mechanics, electrical engineering, medicine, biology, ecology, etc. With regard to this matter, we refer the reader to \cite{c4,c5,h2,h3,y2}. Besides impulsive effects, stochastic effects likewise exist in real systems. Therefore, impulsive stochastic differential equations describing these dynamical systems subject to both impulse and stochastic changes have attracted considerable attention. Particularly, the papers \cite{a5,h5,l4} considered the existence of mild solutions for some impulsive neutral stochastic functional differential and integro-differential equations with infinite delay in Hilbert spaces. As the generalization of classic impulsive differential equations, impulsive stochastic differential inclusions in Hilbert spaces have attracted the researchers great interest. Among them, Ren et al \cite{r1} established the controllability of impulsive neutral stochastic functional differential inclusions with infinite delay in an abstract space by means of the fixed point theorem for discontinuous multi-valued operators due to Dhage. On the other hand, fractional differential equations have gained considerable importance due to their application in various sciences, such as physics, mechanics, chemistry, engineering, etc.. In the recent years, there has been a significant development in ordinary and partial differential equations involving fractional derivatives; see the monograph of Kilbas et al \cite{k1} and the papers \cite{a1,a3,b2,l1,l2} and the references therein. The existence of solutions for fractional semilinear differential or integro-differential equations is one of the theoretical fields that investigated by many authors \cite{a2,e1,y1}. Several papers \cite{a4,d3} devoted to the existence of mild solutions for abstract fractional functional differential and integro-differential equations with state-dependent delay in Banach spaces by using fixed point techniques. Recently, the existence, uniqueness and other quantitative and qualitative properties of solutions to various impulsive semilinear fractional differential and integrodifferential systems have been extensively studied in Banach spaces. For example, Balachandran et al \cite{b1}, Chauhan et al \cite{c1}, Debbouche and Baleanu \cite{d2}, Mophou \cite{m1}, Shu et al \cite{s1}. However, the deterministic models often fluctuate due to noise, which is random or at least appears to be so. Therefore, we must move from deterministic problems to stochastic ones. In this paper, we consider the existence of a class of impulsive fractional partial neutral stochastic integro-differential inclusions with state-dependent delay of the form \begin{gather} d D(t,x_t)\in\int_0^t\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}AD(s,x_{s})\,ds\,dt + F(t,x_{\rho(t,x_t)})\,dw(t), \label{e1.1}\\ t\in J=[0,b], t\neq t_k, k=1,\dots, m,\nonumber \\ x_0=\varphi\in\mathcal{B}, \label{e1.2} \\ \Delta x(t_k)=I_k(x_{t_k}), \quad k=1,\dots, m, \label{e1.3} \end{gather} where the state $x(\cdot)$ takes values in a separable real Hilbert space $H$ with inner product $(\cdot,\cdot)$ and norm $\|\cdot\|$, $1 < \alpha < 2$, $A: D(A)\subset H \to H$ is a linear densely defined operator of sectorial type on $H$. The time history $x_t:(-\infty,0]\to H$ given by $ x_t(\theta)=x(t + \theta)$ belongs to some abstract phase space $ \mathcal{B}$ defined axiomatically; Let $K$ be another separable Hilbert space with inner product $(\cdot,\cdot)_K$ and norm $\| \cdot\|_K$. Suppose $\{w(t):t\geq0\}$ is a given $K$-valued Brownian motion or Wiener process with a finite trace nuclear covariance operator $Q > 0$ defined on a complete probability space $(\Omega,\mathcal{F},P)$ equipped with a normal filtration $\{\mathcal{F}_t\}_{t\geq0}$, which is generated by the Wiener process $w$. We are also employing the same notation $\|\cdot\|$ for the norm $L(K,H)$, where $L(K,H)$ denotes the space of all bounded linear operators from $K$ into $H$. The initial data $\{\varphi(t):-\infty 0$. There is $n_0\in\mathbb{N}$ such that for all $n > n_0$ and $p \in\mathbb{N}$ \[ \|x_{n+p}-x_n\|_{\mathcal{PC}} =(\sup_{0\leq t\leq b} E\|x_{n+p}(t)-x_n(t)\|^2)^{\frac{1}{2}}<\varepsilon \] for each $t \in[0,b]$. From the above inequality it follows that the sequence $x_n(t)$ is a Cauchy sequence in $L^2(\Omega,H)$; moreover, by the completeness of $L^2(\Omega,H)$ with respect to $\|\cdot\|_{L_2}$, for its limit $x(t) := \lim x_n(t)$, we obtain \[ E\| x_n(t)-x(t)\|^2<\varepsilon^2 \] for all $ n > n_0$. Consequently, $\|x_n-x\|_{\mathcal{PC}}\to0$ as $ n \to\infty$. Next, we need to show that $x \in \mathcal{PC}$. In fact, we verify that $x$ is continuous. By \[ x(t + \Delta t) - x(t) = x(t + \Delta t) - x_n(t + \Delta t) + x_n(t + \Delta t) - x_n(t) + x_n(t) - x(t), \] it follows that \begin{align*} E\| x(t + \Delta t) - x(t) \|^2 &\leq 3E\| x(t + \Delta t) - x_n(t + \Delta t)\|^2 \\ &\quad+3 E\| x_n(t + \Delta t) - x_n(t)\|^2 +3 E\| x_n(t) - x(t)\|^2. \end{align*} Using the uniform convergence of $x_n$ to $x$ with respect to $\|\cdot\|_{L_2}$ and the continuity of $x_n$, the continuity of $x$ follows. The proof is complete. \end{proof} To simplify notation, we put $t_0 = 0, t_{m+1} = b$ and for $x \in \mathcal{PC}$, we denote by $\hat{x}_k\in C([t_k, t_{k+1}];L_2(\Omega,H))$, $k = 0, 1, \dots , m$, the function given by \[ \hat{x}_k(t):=\begin{cases} x(t) & \text{for } t\in(t_k,t_{k+1}] ,\\ x(t_k^{+}) & \text{for } t=t_k. \end{cases} \] Moreover, for $B \subseteq\mathcal{PC}$ we denote by $\hat{B_k}$, $k = 0, 1,\dots , m$, the set $\hat{B_k} = \{\hat{x}_k : x\in B\}$. The notation $B_{r}(x,H)$ stands for the closed ball with center at $x$ and radius $r > 0$ in $H$. \begin{lemma} \label{lem2.2} A set $B \subseteq \mathcal{PC}$ is relatively compact in $\mathcal{PC}$ if, and only if, the set $\hat{B_k}$ is relatively compact in $C([t_k,t_{k+1}];L_2(\Omega,H))$, for every $k = 0, 1,\dots, m$. \end{lemma} \begin{proof} Let $B \subseteq \mathcal{PC}$ be a subset and $\{x^{(i)}(\cdot)\}$ be any sequence of $B$. Since $\hat{B_0}$ is a relatively compact subset of $C([0, t_1];L_2(\Omega,H))$. Then, there exists a subsequence of $x^{(i)}$, labeled $\{x_1^{(i)}\}\subset B$, and $x_1 \in C([0, t_1];L_2(\Omega,H))$, such that $$ x_1^{(i)} \to x_1 \quad \text {in } C([0, t_1];L_2(\Omega,H)) \quad \text {as } i \to\infty . $$ Similarly, $\hat{B_k}$ is a relatively compact subset of $C([t_k, t_{k+1}];L_2(\Omega,H))$, for $k=1,2,\dots,m$. Then, there exists a subsequence of $x^{(i)}$, labeled $\{x_k^{(i)}\}\subset B$, such that $x_k \in C([t_k, t_{k+1}];L_2(\Omega,H))$, and $$ x_k^{(i)} \to x^{k} \quad \text {in } C([t_k, t_{k+1}];L_2(\Omega,H)) \text { as } i \to\infty . $$ Setting \[ x(t)= \begin{cases} x_1(t), & t\in [0,t_1], \\ x_2(t), & t\in (t_1,t_2], \\ \dots\\ x_{m}(t), & t\in (t_{m},b], \end{cases} \] then $$ x_{m}^{(i)} \to x\quad \text {in } \mathcal{PC} \text{ as } i \to\infty . $$ Thus, the set $B$ is relatively compact. If set $B \subseteq \mathcal{PC}$ is relatively compact in $\mathcal{PC}$ and $\{x^{(i)}(\cdot)\}$ be any sequence of $B$. Then, for each $t\in[0,t_1]$, there exists a subsequence of $x^{(i)}$, labeled $\{x_1^{(i)}\}\subset B, $ and $x_1 \in \mathcal{PC}$, such that $x_1^{(i)} \to x_1$ in $ \mathcal{PC}$ as $i \to\infty $. From the definition of the set $\hat{B}_0$, we can get $$ \hat{x}_1^{(i)} \to \hat{x}_1 \quad \text{in } C([0,t_1];L_2(\Omega,H)) \text { as } i \to\infty . $$ Similarly, for each $t\in[t_k,t_{k+1}](k=1,2,\dots,m)$, there exists a subsequence of $x^{(i)}$, labeled $\{x_k^{(i)}\}\subset B$ and $x_k \in \mathcal{PC}$, such that $x_k^{(i)} \to x_k$ in $ \mathcal{PC}$ as $i \to\infty $. From the definition of the set $\hat{B}_k$, we can get $$ \hat{x}_k^{(i)} \to \hat{x}_k \quad \text {in } C([t_k, t_{k+1}];L_2(\Omega,H)) \text { as } i \to\infty . $$ Thus, the set $ \hat{B_k}$ is relatively compact in $C([t_k, t_{k+1}];L_2(\Omega,H))$, for every $k = 0, 1,\dots , m$. The proof is complete. \end{proof} In this article, we assume that the phase space $(\mathcal{B},\|\cdot\|_{\mathcal{B}})$ is a seminormed linear space of $\mathcal{F}_0$-measurable functions mapping $(-\infty,0]$ into $H$, and satisfying the following fundamental axioms due to Hale and Kato (see e.g., in \cite{h1}). \begin{itemize} \item[(A)] If $x : (-\infty,\sigma+ b]\to H$, $b > 0$, is such that $x|_{[\sigma,\sigma+b]}\in C([\sigma,\sigma+b],H)$ and $x_{\sigma} \in\mathcal{B}$, then for every $t \in [\sigma,\sigma+b]$ the following conditions hold: \begin{itemize} \item[(i)] $x_t$ is in $\mathcal{B}$; \item[(ii)] $\| x(t)\|\leq \tilde{H}\| x_t\|_{\mathcal{B}} $; \item[(iii)] $\| x_t\|_{\mathcal{B}}\leq K(t-\sigma) \sup\{\| x(s)\|: \sigma \leq s \leq t\}+M(t-\sigma)\| x_{\sigma} \|_{\mathcal{B}}$, where $\tilde{H} \geq 0$ is a constant; $K,M : [0,\infty)\to[1,\infty)$, $K$ is continuous and $M$ is locally bounded, and $\tilde{H},K,M$ are independent of $x(\cdot)$. \end{itemize} \item[(B)] For the function $x(\cdot)$ in (A), the function $t \to x_t$ is continuous from $[\sigma,\sigma+b]$ into $\mathcal{B}$. \item[(C)] The space $\mathcal{B}$ is complete. \end{itemize} The next result is a consequence of the phase space axioms. \begin{lemma} \label{lem2.3} Let $x: (-\infty,b]\to H$ be an $\mathcal{F}_t$-adapted measurable process such that the $\mathcal{F}_0$-adapted process $x_0=\varphi(t)\in L_2^{0}(\Omega, \mathcal{B})$ and $x|_{J}\in \mathcal{PC}(J,H)$, then \[ \| x_{s}\|_{\mathcal{B}} \leq M_{b} E\| \varphi\|_{\mathcal{B}}+K_{b} \sup_{0\leq s\leq b}E\| x(s)\|, \] where $K_{b} = \sup\{K(t):0\leq t\leq b\}$, $M_{b} = \sup\{M(t):0\leq t\leq b\}$. \end{lemma} \begin{proof} For each fixed $x\in H$, we consider the function $\xi(t)$ defined by $\xi(t) = \sup\{\|x_{s}\|_{\mathcal{B}}: 0 \leq s \leq t\}$, $0 \leq t \leq b$. Obviously, $\xi$ is increasing. This combined with the phase space axioms, we have \begin{align*} \xi(t) &\leq M(t) \| \varphi\|_{\mathcal{B}}+K(t) \sup_{0\leq s\leq t}\| x(s)\|\\ &\leq M_{b} \| \varphi\|_{\mathcal{B}}+K_{b}\| x(t)\|. \end{align*} Since $E\| \varphi\|_{\mathcal{B}}<\infty, E\|x(t)\|<\infty$, the previous inequality holds. Consequently \begin{align*} E(\xi(t)) &\leq E(M_{b} \| \varphi\|_{\mathcal{B}}+K_{b}\| x(t)\|)\\ &\leq M_{b} E\| \varphi\|_{\mathcal{B}}+K_{b} \sup_{0\leq s\leq b}E\| x(s)\| \end{align*} for each $t\in J$. By the definition of $\xi$, we have \[ \xi(b)=E(\xi(b))\leq M_{b} E\| \varphi\|_{\mathcal{B}}+K_{b} \sup_{0\leq s\leq b}E\| x(s)\|, \] and $\|x_{s}\|_{\mathcal{B}}\leq\xi(b)$ for each $s\in J$; therefore, \[ \| x_{s}\|_{\mathcal{B}}\leq M_{b} E\| \varphi\|_{\mathcal{B}}+K_{b} \sup_{0\leq s\leq b}E\| x(s)\|. \] The proof is complete. \end{proof} Let $\mathcal{P}(H)$ denote all the nonempty subsets of $H$. Let $\mathcal{P}_{bd,cl}(H) $, $\mathcal{P}_{cp,cv}(H) $, $\mathcal{P}_{bd,cl,cv}(H) $, and $\mathcal{P}_{cd}(H) $ denote respectively the family of all nonempty bounded-closed, compact-convex, bounded-closed-convex and compact-acyclic subsets of $H$ (see \cite{f1}). For $x \in H $ and $Y , Z \in \mathcal{P}_{bd,cl}(H)$, we denote by $D(x,Y)=\inf\{\| x-y\|:y\in Y\}$ and $\tilde{\rho}(Y,Z)=\sup_{a\in Y}D(a,Z)$, and the Hausdorff metric $H_{d}:\mathcal{P}_{bd,cl}(H)\times \mathcal{P}_{bd,cl}(H)\to \mathbb{R}^{+}$ by $H_{d}(A,B)=\max\{\tilde{\rho}(A,B),\tilde{\rho}(B,A)\}$. A multi-valued map $ G$ is called upper semicontinuous (u.s.c.) on $H$ if, for each $x_0\in H$, the set $G(x_0)$ is a nonempty, closed subset of $H$ and if, for each open set $S$ of $H$ containing $ G(x_0)$, there exists an open neighborhood $S$ of $x_0$ such that $ G(S) \subseteq V$. $ F$ is said to be completely continuous if $ G(V)$ is relatively compact, for every bounded subset $V \subseteq H$. If the multi-valued map $G$ is completely continuous with nonempty compact values, then $ G$ is u.s.c. if and only if $ F$ has a closed graph, i.e. $x_n\to x_{*}, y_n\to y_{*}, y_n \in G(x_n)$ imply $y_{*}\in G(x_{*})$. A multi-valued map $ G: J\to \mathcal{P}_{bd,cl,cv} (H) $ is measurable if for each $x\in H$, the function $t \mapsto D(x, G(t))$ is a measurable function on $J$. \begin{definition}[\cite{f1}] \label{def2.6} \rm Let $ G: H\to \mathcal{P}_{bd,cl} (H) $ be a multi-valued map. Then $ G$ is called a multi-valued contraction if there exists a constant $\kappa\in(0,1)$ such that for each $ x, y \in H$ we have \[ H_{d}( G(x)- G(y))\leq \kappa \| x-y\|. \] The constant $\kappa$ is called a contraction constant of $G$. \end{definition} A closed and linear operator $A$ is said to be sectorial of type $\omega$ if there exist $ 0 < \theta < \pi/2$, $M > 0$ and $\omega\in \mathbb{R}$ such that its resolvent exists outside the sector $\omega+S_{\theta}:=\{\omega+\lambda:\lambda\in\mathbb{C}|\arg(-\lambda)<\theta\}$ and $\|(\lambda-A)^{-1}\|\leq\frac{M}{|\lambda-\omega|},\lambda \notin\omega+S_{\theta}$. To give an operator theoretical approach we recall the following definition. \begin{definition}[\cite{c3}] \label{def2.7} \rm Let $A$ be a closed and linear operator with domain $D(A)$ defined on a Hilbert space $H$. We call $A$ the generator of a solution operator if there exist $\omega\in \mathbb{R}$ and a strongly continuous function $S_{\alpha}:\mathbb{R}^{+} \to L(H)$ such that $\{\lambda^{\alpha}: \ \text{Re}(\lambda)>\omega\}\subset\rho(A)$ and $\lambda^{\alpha-1}(\lambda^{\alpha}-A)^{-1}x=\int_0^\infty e^{-\lambda t}S_{\alpha}(t)dt,\text{Re}(\lambda)>\omega,x\in H$. In this case, $S_{\alpha}(\cdot)$ is called the solution operator generated by $A$. \end{definition} We note that, if $A$ is sectorial of type $\omega$ with $0 < \theta < \pi(1-\frac{\alpha}{2})$ then $A$ is the generator of a solution operator given by \[ S_{\alpha}(t)=\frac{1}{2\pi i}\int_{\Sigma}e^{-\lambda t}\lambda^{\alpha-1}(\lambda^{\alpha}-A)^{-1}d\lambda, \] where $\Sigma$ is a suitable path lying outside the sector $\omega+S_{\alpha}$. Cuesta \cite{c3} proved that, if $A$ is a sectorial operator of type $\omega< 0$, for some $M > 0$ and $0 < \theta < \pi(1-\frac{\alpha}{2})$, there is $C> 0$ such that \begin{equation} \label{e2.1} \| S_{\alpha}(t)\|\leq \frac{CM}{1+|\omega|t^{\alpha}}, \ t\geq0. \end{equation} Moreover, we have the following results. \begin{lemma}[\cite{c3}] \label{lem 2.4} Let $S_{\alpha}(t)$ be a solution operator on $H$ with generator $A$. Then, we have \begin{itemize} \item[(a)] $S_{\alpha}(t)D(A)\subset D(A)$ and $AS_{\alpha}(t)x=S_{\alpha}(t)Ax$ for all $x \in D(A), t \geq 0;$ \item[(b)] Let $x \in D(A)$ and $t \geq 0$. Then $S_{\alpha}(t)x=x+ \int_0^t\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}A S_{\alpha}(s)xds;$ \item[(c)] Let $x \in H$ and $t > 0$. Then $\int_0^t\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}S_{\alpha}(s)x\,ds\in D(A)$ and $$ S_{\alpha}(t)x =x+ A\int_0^t\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}S_{\alpha}(s)xds. $$ \end{itemize} \end{lemma} Note that the Laplace transform of the abstract function $f \in L^2(\mathbb{R}^{+},L(K,H)) $ is defined by \[ \tilde{f}(\varsigma)=\int_0^\infty e^{-\varsigma t}f(t)dw(t). \] Now we consider the problem \begin{gather} \label{e2.2} dx(t)=\int_0^t\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}Ax(s)\,ds\,dt + f(t)dw(t), \quad t> 0, 1 < \alpha < 2, \\ \label{e2.3} x_0=\varphi\in H. \end{gather} Formally applying the Laplace transform, we obtain \[ \lambda\tilde{x}(\varsigma)-\varphi=\lambda^{1-\alpha}A\tilde{x}(\varsigma) +\tilde{f}(\lambda)dw(\lambda), \] which establishes the result \[ \lambda\tilde{x}(\varsigma)=\lambda^{\alpha-1}R(\lambda^{\alpha},A)\varphi +\lambda^{\alpha-1}R(\lambda^{\alpha},A)\tilde{f}(\lambda)dw(\lambda). \] This implies that \[ x(t)=S_{\alpha}(t)\varphi+\int_0^tS_{\alpha}(t-s)f(s)dw(s). \] Let $x : (-\infty, b] \to H$ be a function such that $x, x' \in \mathcal{PC}$. If $x$ is a solution of \eqref{e1.1}-\eqref{e1.3}, from the partial neutral integro-differential inclusions theory, we obtain \[ x(t)\in S_{\alpha}(t)[\varphi(0)- G(0,\varphi)] + G(t,x_t)+\int_0^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s), \quad t\in [0,t_1]. \] By using that $x(t_1^{+}) = x(t_1^{-}) + I_k(x_{t_1})$, for $t \in(t_1, t_2] $ we have \begin{align*} x(t)&\in S_{\alpha}(t-t_1)[x(t_1^{+})- G(t_1,x_{t^{+}_1})] + G(t,x_t) +\int_{t_1}^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s)\\ &=S_{\alpha}(t-t_1)[x(t_1^{-})+I_1(x_{t_1})- G(t_1,x_{t^{+}_1})] + G(t,x_t) \\ &\quad +\int_{t_1}^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s). \end{align*} By repeating the same procedure, we can easily deduce that \begin{align*} x(t)&\in S_{\alpha}(t-t_k)[x(t_k^{-})+I_k(x_{t_k})- G(t_1,x_{t^{+}_k})] + G(t,x_t) \\ &\quad +\int_{t_k}^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s) \end{align*} holds for any $t \in(t_k,t_{k+1}], k=2,\dots,m$. This expression motivates the following definition. \begin{definition} \label{def2.8} \rm An $\mathcal{F}_t$-adapted stochastic process $x : (-\infty,b]\to H$ is called a mild solution of the system \eqref{e1.1}-\eqref{e1.3} if $x_0 = \varphi, x_{\rho(s,x_{s})} \in \mathcal{B}$ for every $s \in J$ and $\Delta x(t_k)=I_k(x_{t_k}), k=1,\dots, m$, the restriction of $x(\cdot)$ to the interval $(t_k, t_{k+1}] (k= 0, 1,\dots , m) $ is continuous, and \[ x(t)\in \begin{cases} S_{\alpha}(t)[\varphi(0)- G(0,\varphi)] + G(t,x_t)\\ +\int_0^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s), &t\in [0,t_1], \\[3pt] S_{\alpha}(t-t_1)[x(t_1^{-})+I_1(x_{t_1})- G(t_1,x_{t^{+}_1})] + G(t,x_t)\\ +\int_{t_1}^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s), &t\in (t_1,t_2], \\ \dots\\ S_{\alpha}(t-t_{m})[x(t_{m}^{-})+I_{m}(x_{t_{m}})- G(t_{m},x_{t^{+}_{m}})] + G(t,x_t)\\ +\int_{t_{m}}^t S_{\alpha}(t-s)F(s,x_{\rho(s,x_{s})})dw(s), &t\in (t_{m},b]. \end{cases} \] \end{definition} Now we have a nonlinear alternative of Leray-Schauder type for multivalued maps due to O'Regan. \begin{lemma}[\cite{o1}] \label{lem2.5} Let $H$ be a Hilbert space with $V$ an open,convex subset of $H$ and $ y\in H$. Suppose \begin{itemize} \item[(a)] $ \Phi :\overline{V} \to \mathcal{P}_{cd}(H)$ has closed graph, and \item[(b)] $ \Phi :\overline{V} \to \mathcal{P}_{cd}(H)$ is a condensing map with $\Phi(\overline{V})$ a subset of a bounded set in $H$ hold. \end{itemize} Then either \begin{itemize} \item[(i)] $\Phi$ has a fixed point in $\overline{V};$ or \item[(ii)] There exist $y \in \partial V$ and $\lambda\in(0,1)$ with $y \in\lambda \Phi(y)+(1-\lambda)\{y_0\}$. \end{itemize} \end{lemma} \section{Main results} In this section we shall present and prove our main result. Assume that $\rho :J \times \mathcal{B}\to (-\infty,b]$ is continuous. In addition, we make the following hypotheses: \begin{itemize} \item[(H1)] The function $t \to \varphi_t$ is continuous from $\mathcal{R}(\rho^{-})=\{\rho(s,\psi)\leq 0, (s,\psi)\in J\times \mathcal{B}\}$ into $\mathcal{B}$ and there exists a continuous and bounded function $J^{\varphi}:\mathcal{R}(\rho^{-})\to(0,\infty)$ such that $\| \varphi_t\|_{\mathcal{B}}\leq J^{\varphi}(t)\| \varphi\|_{\mathcal{B}}$ for each $t\in \mathcal{R}(\rho^{-})$. \item[(H2)] The multi-valued map $F:J\times\mathcal{B}\to \mathcal{P}_{bd,cl,cv}(L(K,H));$ for each $t \in J$, the function $F(t, \cdot) : \mathcal{B}\to \mathcal{P}_{bd,cl,cv}(L(K,H))$ is u.s.c. and for each $\psi \in \mathcal{B}$, the function $F(\cdot, \psi)$ is measurable; for each fixed $\psi\in\mathcal{B}$, the set \[ S_{F,\psi}= \{f \in L^2(J,L(K,H)) : f(t)\in F(t,\psi) \quad \text{for a.e } t \in J\} \] is nonempty. \item[(H3)] There exists a positive function $l: J\to \mathbb{R}^{+}$ such that the function $s \mapsto(\frac{1}{1+|\omega|(t-s)^{\alpha}})^2l(s)$ belongs to $L^{1}([0, t], \mathbb{R}^{+}),t\in J$, and \[ \limsup_{\|\psi\|^2_{\mathcal{B}}\to\infty}\frac{\| F(t,\psi)\|^2}{l(t)\| \psi\|^2_{\mathcal{B}}}= \gamma \] uniformly in $t\in J$ for a nonnegative constant $\gamma$, where \[ \| F (t,\psi)\|^2= \sup\{E\| f \|^2: f\in F (t,\psi)\}. \] \item[(H4)] The function $G:J\times\mathcal{B}\to H$ is continuous and there exist $L,L_1>0$ such that \begin{gather*} E\| G(t,\psi_1)- G(t,\psi_2)\|^2\leq L\| \psi_1-\psi_2\|^2_{\mathcal{B}}, \quad t\in J, \psi_1,\psi_2\in \mathcal{B}, \\ E\| G(t,\psi)\|^2\leq L_1(\| \psi\|^2_{\mathcal{B}}+1), \ \ \ t\in J, \psi\in \mathcal{B}, \end{gather*} with $4[(CM)^2+1]LK^2_{b}< 1$. \item[(H5)] The functions $I_k: \mathcal{B}\to H$ are completely continuous and there exist constants $c_k$ such that \[ \limsup_{\|\psi\|^2_{\mathcal{B}}\to\infty} \frac{E\| I_k(\psi)\|^2}{\|\psi\|^2_{\mathcal{B}}}= c_k \] for every $\psi \in\mathcal{B}$, $k = 1,\dots ,m$. \end{itemize} \begin{remark} \label{rmk3.1} \rm Let $\varphi\in \mathcal{B} $ and $t \leq 0$. The notation $\varphi_t$ represents the function defined by $\varphi_t(\tau)=\varphi(t+\theta)$. Consequently, if the function $x(\cdot)$ in axiom (A) is such that $x_0=\varphi$, then $x_t=\varphi_t $. We observe that $\varphi_t$ is well-defined for $t < 0$ since the domain of $\varphi$ is $(-\infty,0]$. We also note that, in general, $\varphi_t\notin\mathcal{B};$ consider, for instance, a discontinuous function in $C_{r} \times L^{p}(h,H)$ for $r> 0$ (see \cite{h4}). \end{remark} \begin{remark} \label{rmk3.2}\rm The condition (H1) is frequently verified by continuous and bounded functions. In fact, if $\mathcal{B}$ verifies axiom (C$_2$) in the nomenclature of \cite{h4}, then there exists $\tilde{L}> 0 $ such that $\| \varphi\|_{\mathcal{B}}\leq \tilde{L}\sup_{\tau\leq0}\|\varphi(\tau)\|$ for every $\varphi\in\mathcal{B}$ continuous and bounded, see \cite[Proposition 7.1.1]{h4} for details. Consequently, $$ \| \varphi_t\|_{\mathcal{B}}\leq \tilde{L}\frac{\sup_{\tau\leq0}\varphi(\tau)} {\| \varphi\|_{\mathcal{B}}}, $$ for every continuous and bounded function $\varphi\in\mathcal{B}\setminus\{0\}$ and every $t \leq 0$. We also observe that the space $C_{r}\times L^{p}(h,H)$ verifies axiom (C$_2$) see \cite[p. 10]{h4} for details. \end{remark} \begin{lemma} \label{lem3.1} Let $x:(-\infty,b]\to H$ such that $x_0=\varphi$ and $x|_{[0,b]}\in \mathcal{PC}(J,H)$. If (H1) be hold, then \[ \| x_{s}\|_{\mathcal{B}}\leq (M_{b}+J_0^{\varphi}) \| \varphi\|_{\mathcal{B}}+K_{b}\sup\{\| x(\theta)\|; \theta\in[0,\max\{0,s\}]\},s\in \mathcal{R}(\rho^{-})\cup J, \] where $J_0^{\varphi}=\sup_{t\in \mathcal{R}(\rho^{-})}J^{\varphi}(t)$. \end{lemma} \begin{proof} For any $s\in \mathcal{R}(\rho^{-})$, by (H1), we have \[ \| x_{s}\|_{\mathcal{B}} \leq\| \varphi_{s}\|_{\mathcal{B}} \leq J^{\varphi}(s)\| \varphi\|_{\mathcal{B}}\leq J_0^{\varphi}\| \varphi\|_{\mathcal{B}}. \] For any $s\in[0,b]$, $x\in \mathcal{PC}(J,H)$. Using the phase spaces axioms, we have \begin{align*} \| x_{s}\|_{\mathcal{B}} &\leq M(s)\| \varphi\|_{\mathcal{B}}+K(s) \sup\{\| x(s)\|:0\leq s\leq t\}\\ &\leq M_{b}\| \varphi\|_{\mathcal{B}}+K_{b} \sup\{\| x(s)\|:0\leq s\leq t\}. \end{align*} Then, for $s\in(-\infty,b]$, we have \[ \| x_{s}\|_{\mathcal{B}}\leq (M_{b}+J_0^{\varphi}) \| \varphi\|_{\mathcal{B}}+K_{b}\sup\{\| x(\theta)\|; \theta\in[0,\max\{0,s\}]\},s\in \mathcal{R}(\rho^{-})\cup J. \] The proof is complete. \end{proof} \begin{lemma}[\cite{l3}] \label{lem3.2} Let $J$ be a compact interval and $H$ be a Hilbert space. Let $F$ be a multivalued map satisfying {\rm (H2)} and $\Gamma$ be a linear continuous operator from $L^2(J, H)$ to $C(J, H)$. Then the operator $\Gamma\circ S_{F}: C(J, H)\to \mathcal{P}_{cp,cv}(C(J, H)) $ is a closed graph in $C(J, H)\times C(J, H )$. \end{lemma} \begin{theorem} \label{thm3.1} Let {\rm (H1)--(H5)} be satisfied and $x_0 \in L^{0}_2 ( \Omega,H)$, with $\rho(t,\psi) \leq t$ for every $(t,\psi) \in J\times \mathcal{B}$. Then problem \eqref{e1.1}-\eqref{e1.3} has at least one mild solution on $J$, provided that \begin{equation} \max_{1\leq k\leq m} \{9(CM)^2[1+2K_{b}^2c_k +2K_{b}^2L_1]+6K_{b}^2L_1\}<1. \end{equation} \end{theorem} \begin{proof} Consider the space $\mathcal{BPC}=\{x:(-\infty,b]\to H; x_0=0, x|_{J}\in\mathcal{PC}\}$ endowed with the uniform convergence topology and define the multi-valued map $\Phi:\mathcal{BPC}\to \mathcal{P}(\mathcal{BPC})$ by $\Phi x$ the set of $ h\in \mathcal{BPC}$ such that \[ h(t)= \begin{cases} 0, & t\in (-\infty,0], \\[3pt] S_{\alpha}(t)[\varphi(0)- G(0,\varphi)] + G(t,\bar{x}_t)+\int_0^t S_{\alpha}(t-s)f(s)dw(s), &t\in [0,t_1], \\[3pt] S_{\alpha}(t-t_1)[\bar{x}(t_1^{-})+I_1(\bar{x}_{t_1}) - G(t_1,\bar{x}_{t^{+}_1})] + G(t,\bar{x}_t)\\ +\int_{t_1}^t S_{\alpha}(t-s)f(s)dw(s), & t\in (t_1,t_2], \\ \dots\\ S_{\alpha}(t-t_{m})[\bar{x}(t_{m}^{-})+I_{m}(\bar{x}_{t_{m}}) - G(t_{m},\bar{x}_{t^{+}_{m}})] + G(t,\bar{x}_t)\\ +\int_{t_{m}}^t S_{\alpha}(t-s)f(s)dw(s), &t\in (t_{m},b], \end{cases} \] where $f\in S_{F,\bar{x}_{\rho}}= \{ f \in L^2 (L(K, H)) : f (t) \in F(t,\bar{x}_{\rho(s,\bar{x}_t)})\ \text{a.e. } t \in J \}$ and $\bar{x}:(-\infty,0]\to H$ is such that $\bar{x}_0=\varphi$ and $\bar{x}=x$ on $J$. In what follows, we aim to show that the operator $\Phi$ has a fixed point, which is a solution of the problem \eqref{e1.1}-\eqref{e1.3}. Let $\bar{\varphi}:(-\infty,0)\to H$ be the extension of $(-\infty,0]$ such that $\bar{\varphi}(\theta)=\varphi(0)=0$ on $J$ and $J^{\varphi}_0=\sup\{J^{\varphi}(s):s\in\mathcal{R}(\rho^{-})\}$. We now show that $\Phi$ satisfies all the conditions of Lemma \ref{lem2.5}. The proof will be given in several steps. \smallskip \noindent\textbf{Step 1.} We shall show there exists an open set $V\subseteq \mathcal{BPC}$ with $x \in\lambda \Phi x$ for $\lambda\in(0, 1) $ and $ x\notin \partial V$. Let $\lambda\in (0, 1)$ and let $x\in\lambda \Phi x$, then there exists an $f\in S_{F,\bar{x}_{\rho}}$ such that we have \[ x(t)=\begin{cases} \lambda S_{\alpha}(t)[\varphi(0)- G(0,\varphi)] +\lambda G(t,\bar{x}_t)+\lambda\int_0^t S_{\alpha}(t-s)f(s)dw(s), &t\in [0,t_1], \\[3pt] \lambda S_{\alpha}(t-t_1)[\bar{x}(t_1^{-})+I_1(\bar{x}_{t_1}) - G(t_1,\bar{x}_{t^{+}_1})] +\lambda G(t,\bar{x}_t)\\ +\lambda\int_{t_1}^t S_{\alpha}(t-s)f(s)dw(s), &t\in (t_1,t_2], \\ \dots\\ \lambda S_{\alpha}(t-t_{m})[\bar{x}(t_{m}^{-})+I_{m}(\bar{x}_{t_{m}})- G(t_{m},\bar{x}_{t^{+}_{m}})] +\lambda G(t,\bar{x}_t)\\ +\lambda\int_{t_{m}}^t S_{\alpha}(t-s)f(s)dw(s), & t\in (t_{m},b], \end{cases} \] for some $\lambda\in (0, 1)$. It follows from assumption (H3) that there exist two nonnegative real numbers $a_1$ and $a_2$ such that for any $\psi\in \mathcal{B}$ and $t\in J$, \begin{equation} \label{e3.2} \| F(t,\psi)\|^2 \leq a_1l(t)+a_2l(t)\| \psi\|^2_{\mathcal{B}}. \end{equation} On the other hand, from condition (H5), we conclude that there exist positive constants $\epsilon_k(k=1,\dots,m),\gamma_1$ such that, for all $\| \psi\|_{\mathcal{B}}^2>\gamma_1$, \begin{gather} E\| I_k(\psi)\|^2 \leq (c_k+\epsilon_k) \| \psi\|^2_{\mathcal{B}}, \nonumber \\ \max_{1\leq k\leq m} \{9(CM)^2[1+2K_{b}^2(c_k+\epsilon_k) +2K_{b}^2L_1]+6K_{b}^2L_1\}<1. \label{e3.3} \end{gather} Let \begin{gather*} F_1 = \{\psi: \| \psi\|^2_{\mathcal{B}}\leq \gamma_1\}, \ \ \ F_2 = \{\psi: \| \psi \|^2_{\mathcal{B}}> \gamma_1\},\\ C_1= \max \{ E\| I_k(\psi)\|^2, x\in F_1 \}. \end{gather*} Therefore, \begin{equation} \label{e3.4} E\| I_k(\psi)\|^2 \leq C_1+(c_k+\epsilon_k)\|\psi\|_{\mathcal{B}}^2. \end{equation} Then, by (H4), \eqref{e3.2} and \eqref{e3.4}, from the above equation, for $t \in [0,t_1]$, we have \begin{align*} E\| x(t)\|^2 &\leq 3E\| S_{\alpha}(t)[\varphi(0)- G(0,\varphi)]\|^2 +3E\| G(t,\bar{x}_t)\|^2\\ &\quad+3E\big\|\int_0^t S_{\alpha}(t-s)f(s)dw(s)\big\|^2\\ &\leq 6(CM)^2[E\| \varphi(0) \|^2+L_1(\| \varphi \|^2_{\mathcal{B}}+1)]+3L_1(\| \bar{x}_t \|^2_{\mathcal{B}}+1)\\ &\quad+3(CM)^2\operatorname{Tr}(Q)\int_0^{t} \Big(\frac{1}{1+|\omega|(t-s)^{\alpha}}\Bigr)^2[a_1l(s)+a_2l(s)\| \bar{x}_{\rho(s,\bar{x}_{s})}\|^2_{\mathcal{B}}]ds\\ &\leq 6(CM)^2[\tilde{H}^2E\| \varphi \|^2_{\mathcal{B}}+L_1(\| \varphi \|^2_{\mathcal{B}}+1)]+3L_1(\| \bar{x}_t \|^2_{\mathcal{B}}+1)\\ &\quad+3(CM)^2\operatorname{Tr}(Q)a_1\int_0^{t_1} \Big(\frac{1}{1+|\omega|(t_1-s)^{\alpha}}\Bigr)^2l(s)ds\\ &\quad +3(CM)^2\operatorname{Tr}(Q)a_2\int_0^{t} \Big(\frac{1}{1+|\omega|(t-s)^{\alpha}}\Bigr)^2l(s)\| \bar{x}_{\rho(s,\bar{x}_{s})}\|^2_{\mathcal{B}}ds. \end{align*} Similarly, for any $t\in (t_k, t_{k+1}]$, $k = 1, \dots ,m$, we have \begin{align*} &E\| x(t)\|^2\\ &\leq3E\| S_{\alpha}(t-t_k)[\bar{x}(t_k^{-})+I_k(\bar{x}_{t_k})- G(t_k,\bar{x}_{t^{+}_k})]\|^2 +3E\| G(t,\bar{x}_t)\|^2\\ &\quad +3E\big\|\int_{t_k}^t S_{\alpha}(t-s)f(s)dw(s)\big\|^2\\ &\leq9(CM)^2[E\| \bar{x}(t_k^{-}) \|^2+C_1+(c_k+\epsilon_k)\|\bar{x}_{t_k}\|^2_{\mathcal{B}} +L_1(\| \bar{x}_{t^{+}_k}\|^2_{\mathcal{B}}+1)]\\ &\quad+3L_1(\| \bar{x}_t \|^2_{\mathcal{B}}+1) +3(CM)^2a_1\operatorname{Tr}(Q)\int_{t_k}^{t_{k+1}} \Big(\frac{1}{1+|\omega|(t_{k+1}-s)^{\alpha}}\Bigr)^2l(s)ds\\ &\quad+3(CM)^2a_2\operatorname{Tr}(Q)\int_{t_k}^{t} \Big(\frac{1}{1+|\omega|(t-s)^{\alpha}}\Bigr)^2l(s)\| \bar{x}_{\rho(s,\bar{x}_{s})}\|^2_{\mathcal{B}}ds. \end{align*} Then, for all $t \in [0, b]$, we have \begin{align*} &E\| x(t)\|^2\\ &\leq \widetilde{M}+9(CM)^2[E\| \bar{x}(t_k^{-}) \|^2+(c_k+\epsilon_k)\|\bar{x}_{t_k}\|^2_{\mathcal{B}} +L_1\| \bar{x}_{t^{+}_k}\|^2_{\mathcal{B}}]\\ &\quad+3L_1\| \bar{x}_t \|^2_{\mathcal{B}} +3(CM)^2a_2\operatorname{Tr}(Q)\int_0^{t} \Big(\frac{1}{1+|\omega|(t-s)^{\alpha}}\Bigr)^2l(s)\| \bar{x}_{\rho(s,\bar{x}_{s})}\|^2_{\mathcal{B}}ds, \end{align*} where \begin{align*} \widetilde{M} &=\max\Big\{6(CM)^2[\tilde{H}^2E\| \varphi \|^2_{\mathcal{B}}+L_1(\| \varphi \|^2_{\mathcal{B}}+1)]+3L_1\\ &\quad+3(CM)^2\operatorname{Tr}(Q)a_1\int_0^{t_1}\Big(\frac{1}{1+|\omega|(b-s)^{\alpha}}\Bigr)^2l(s)ds,\ 9(CM)^2(C_1 +L_1)\\ &\quad+3L_1 +3(CM)^2a_1\operatorname{Tr}(Q)\int_{t_k}^{t_{k+1}} \Big(\frac{1}{1+|\omega|(t_{k+1}-s)^{\alpha}}\Bigr)^2l(s)ds\Bigr\}. \end{align*} By Lemmas \ref{lem2.3} and \ref{lem3.1}, it follows that $\rho(s,\overline{x}_{s})\leq s, s\in [0,t], t\in [0,b]$ and \begin{equation} \label{e3.5} \| \overline{x}_{\rho(s,\overline{x}_{s})}\|^2_{\mathcal{B}} \leq 2[(M_{b}+J^{\varphi}_0)E\| \varphi\|_{\mathcal{B}}]^2 +2K_{b}^2\sup_{0\leq s \leq b}E\| x(s)\|^2. \end{equation} For each $t \in [0,b]$, we have \begin{align*} E\| x(t)\|{^2} &\leq M_{*} +\{9(CM)^2[1+2K_{b}^2(c_k+\epsilon_k) +2K_{b}^2L_1]+6K_{b}^2L_1\} \sup_{t\in[0,b]}E\| x(t)\|{^2} \\ &\quad +6(CM)^2a_2K_{b}^2\operatorname{Tr}(Q)\int_0^{t} \Big(\frac{1}{1+|\omega|(t-s)^{\alpha}}\Bigr)^2l(s) \sup_{\tau\in[0,s]}E\| x(\tau)\|{^2} ds, \end{align*} where \begin{gather*} \begin{aligned} M_{*}&=\widetilde{M}+9(CM)^2[C_1+(c_k+\epsilon_k)C^{*} +L_1(C^{*}+1)]+3L_1(C^{*}+1)\\ &\quad+3(CM)^2\operatorname{Tr}(Q)a_2C^{*}\int_0^{b} \Big(\frac{1}{1+|\omega|(b-s)^{\alpha}}\Bigr)^2l(s)ds, \end{aligned}\\ C^{*}=2[(M_{b}+J^{\varphi}_0)\|\varphi\|_{\mathcal{B}}]^2. \end{gather*} Since $L_{*}=\max_{1\leq k\leq m} \{9(CM)^2[1+2K_{b}^2(c_k+\epsilon_k) +2K_{b}^2L_1]+6K_{b}^2L_1\}<1$, we have \begin{align*} &\sup_{t\in[0,b]}E\| x(t)\|^2 \\ &\leq\frac{M_{*}}{1-L_{*}} +\frac{6(CM)^2a_2K_{b}^2\operatorname{Tr}(Q)}{1-L_{*}} \int_0^{b}\Big(\frac{1}{1+|\omega|(b-s)^{\alpha}}\Bigr)^2l(s) \sup_{\tau\in[0,s]}E\| x(\tau)\|{^2} ds. \end{align*} Applying Gronwall's inequality in the above expression, we obtain \[ \sup_{t\in[0,b]}E\| x(s)\| ^2\leq \frac{M_{*}}{1-L_{*}} \exp \Big\{\frac{6(CM)^2a_2K_{b}^2\operatorname{Tr}(Q)}{1-L_{*}} \int_0^{b}\Big(\frac{1}{1+|\omega|(b-s)^{\alpha}}\Bigr)^2l(s)ds\Bigr\} \] and, therefore, \[ \|x\|^2_{\mathcal{PC}}\leq\frac{M_{*}}{1-L_{*}} \exp \Big\{\frac{6(CM)^2a_2K_{b}^2\operatorname{Tr}(Q)}{1-L_{*}} \int_0^{b}\Big(\frac{1}{1+|\omega|(b-s)^{\alpha}}\Bigr)^2l(s)ds\Bigr\}<\infty. \] Then, there exists $r^{*}$ such that $\|x\|^2_{\mathcal{PC}}\neq r^{*}$. Set $$ V = \{x\in \mathcal{BPC} :\| x\|^2_{\mathcal{PC}} 0$ imply the continuity in the uniform operator topology. Indeed, the fact of $S_{\alpha}(\cdot)$ is compact in $H$ since it is generated by the dense operator $A$. Thus the set $\{\Phi_2x : x\in \overline{V}\}$ is equicontinuous. The equicontinuities for the other cases $ \tau_1 < \tau_2 \leq 0$ or $ \tau_1\leq 0 \leq \tau_2 \leq b$ are very simple. Next, we prove that $\Phi_2(\overline{V})(t)=\{ h_2(t): h_2(t)\in\Phi_2(\overline{V})\}$ is relatively compact for every $t\in [0,b]$. To this end, we decompose $\Phi_2$ by $\Phi_2(\overline{V}) = \Gamma_1(\overline{V}) + \Gamma_2(\overline{V})$, where the map $\Gamma_1$ is defined by $\Gamma_1 x, x\in \overline{V}$ the set $ \tilde{h}_1$ such that \[ \tilde{h}_1(t)= \begin{cases} \int_0^tS_{\alpha}(t-s)f(s)dw(s), &t\in [0,t_1], \\ \int_{t_k}^tS_{\alpha}(t-s)f(s)dw(s), &t\in (t_1,t_2],\\ \dots\\ \int_{t_{m}}^tS_{\alpha}(t-s)f(s)dw(s), &t\in (t_{m},b], \end{cases} \] and the map $\Gamma_2$ is defined by $\Gamma_2 x, x\in \overline{V}$ the set $ \tilde{h}_2$ such that \[ \tilde{h}_2(t)= \begin{cases} S_{\alpha}(t)\varphi(0), &t\in [0,t_1], \\ S_{\alpha}(t-t_1)[\bar{x}(t_1^{-})+I_1(\bar{x}_{t_1})], &t\in (t_1,t_2], \\ \dots\\ S_{\alpha}(t-t_{m})[\bar{x}(t_{m}^{-})+I_{m}(\bar{x}_{t_{m}})], &t\in (t_{m},b]. \end{cases} \] We now prove that $\Gamma_1(\overline{V}))(t)=\{\tilde{h}_1(t): \tilde{h}_1(t)\in\Gamma_1(\overline{V}))\}$ is relatively compact for every $t\in [0,b]$. Let $00$, we deduce that the set $U_{\varepsilon}(t)=\{\tilde{h}_{1,\varepsilon}(t) : x\in \overline{V}\}$ is relatively compact in $H$ for every $\varepsilon, 0<\varepsilon0$, we deduce that the set $U_{\varepsilon}(t)=\{\tilde{h}_{1,\varepsilon}(t) : x\in \overline{V}\}$ is relatively compact in $H$ for every $\varepsilon, 0<\varepsilon 0$ such that \[ [\widehat{\tilde{h}_2}]_k(t) \in \begin{cases} S_{\alpha}(t-t_k)[\bar{x}(t_k^{-})+I_k(\bar{x}_{t_k})], &t\in (t_k,t_{k+1}), \ x \in \overline{V} _{r''},\\ S_{\alpha}(t_{k+1}-t_k)[\bar{x}(t_k^{-})+I_k(\bar{x}_{t_k})], & t=t_{k+1}, \ x \in \overline{V}_{r''},\\ \bar{x}(t_k^{-})+I_k(\bar{x}_{t_k}), & t=t_k, \ x \in \overline{V}_{r''}, \end{cases} \] where $\overline{V}_{r''}$ is an open ball of radius $r''$. From (H5), it follows that $[\widehat{\tilde{h}_2}]_k(t)$ is relatively compact in $H$, for all $t\in [t_k, t_{k+1}]$, $ k= 1, \dots ,m$. By Lemma \ref{lem2.2}, we infer that $\Gamma_2(\overline{V})$ is relatively compact. Moreover, using the compactness of $\{I_k\} (k= 1, \dots ,m)$ and the continuity of the operator $S_{\alpha}(t)$, for all $t \in [0, b]$, $\Gamma_2(\overline{V})$ is completely continuous, and hence $\Phi_2(\overline{V})$ is completely continuous. As a consequence of the above steps 1-3, we conclude that $\Phi=\Phi_1+\Phi_2$ is a condensing map. All of the conditions of Lemma \ref{lem2.5} are satisfied, we deduce that $\Phi$ has a fixed point $x\in\mathcal{BPC}, $ which is in turn a mild solution of the problem \eqref{e1.1}-\eqref{e1.3}. The proof is complete. \end{proof} \begin{remark} \label{rmk3.3}\rm Note that by the condition $\rho(s,\overline{x}_{s})\leq s$, $s\in [0,t]$, $t\in [0,b]$ and using Lemma \ref{lem3.1}, we have \[ \| \overline{x}_{\rho(s,\overline{x}_{s})}\|_{\mathcal{B}} \leq (M_{b}+J^{\varphi}_0)\| \varphi\|_{\mathcal{B}}+K_{b}\sup\{\| \bar{x}(s)\|:0\leq s \leq t\}. \] By lemma \ref{lem2.3} this implies that \[ \| \overline{x}_{\rho(s,\overline{x}_{s})}\|_{\mathcal{B}} \leq (M_{b}+J^{\varphi}_0)E\| \varphi\|_{\mathcal{B}} +K_{b}\sup_{0\leq s \leq b}E\| x(s)\|, \] and so \eqref{e3.5} holds. \end{remark} \section{Application} Consider the following impulsive fractional partial neutral stochastic functional integro-differential inclusions of the form \begin{gather} \begin{aligned} d D(t,z_t)(x)& \in J_t^{\alpha-1} \Big(\frac{\partial^2}{\partial x^2}-\nu\Big) D(t,z_t)(x)dt\\ &\quad + \int_{-\infty}^t \mu_2(t,s-t,x,z(s-\rho_1(t)\rho_2(\|z(t)\|),x))dw(s),\\ &\quad 0\leq t\leq b,\; 0\leq x\leq \pi, \\ \end{aligned} \label{e4.1} \\ z(t,0)=z(t,\pi)=0, \quad 0\leq t\leq b, z(\tau,x)=\varphi(\tau,x), \quad \tau\leq 0,\; 0\leq x\leq \pi,\\ \triangle z(t_k,x)=\int_{-\infty}^{t_k}\eta_k(s-t_k)z(s,x)ds, \quad k=1,2,\dots,m, \label{e4.4} \end{gather} where $1 < \alpha < 2$, $\nu> 0 $ and $\varphi$ is continuous and $w(t)$ denotes a standard cylindrical Wiener process in $H$ defined on a stochastic space $(\Omega,\mathcal{F},P)$. In this system, $$ D(t,z_t)(x)=z(t,x)-\int_{-\infty}^t \mu_1(s-t)z(s,x) ds. $$ Let $H=L^2([0,\pi])$ with the norm $\|\cdot\|$ and define the operator $A: D(A)\subset H \to H$ is the operator given by $A\omega=\omega''-\nu\omega$ with the domain $$ D(A) :=\{\omega \in H : \omega'' \in H, \omega(0) =\omega(\pi) = 0\}. $$ It is well known that $\Delta x =x''$ is the infinitesimal generator of an analytic semigroup $T (t), t \geq0$ on $H$. Hence, $A$ is sectorial of type $\mu=-\nu< 0$. Let $r \geq 0, 1 \leq p < 1$ and let $h:(-\infty,-r]\to \mathbb{R}$ be a nonnegative measurable function which satisfies the conditions (h-5), (h-6) in the terminology of Hino et al \cite{h4}. Briefly, this means that $h$ is locally integrable and there is a non-negative, locally bounded function $\gamma$ on $(-\infty,0]$ such that $h(\xi+\tau)\leq\gamma(\xi)h(\tau)$ for all $\xi\leq0$ and $\theta\in(-\infty,-r)\setminus N_{\xi}$, where $N_{\xi}\subseteq(-\infty,-r)$ is a set whose Lebesgue measure zero. We denote by $\mathcal{PC}_{r} \times L^2(h ,H)$ the set consists of all classes of functions $\varphi:(-\infty,0]\to X$ such that $\varphi_{|_{[-r,0]}}\in\mathcal{PC}([-r,0],H)$, $\varphi(\cdot)$ is Lebesgue measurable on $(-\infty,-r)$, and $h\| \varphi\|^{p}$ is Lebesgue integrable on $(-\infty,-r)$. The seminorm is given by $$ \| \varphi\|_{\mathcal{B}}=\sup_{-r\leq \tau\leq0}\|\varphi(\tau)\|+\Big(\int_{-\infty}^{-r}h(\tau)\| \varphi\|^{p}d\tau\Bigr)^{1/p}. $$ The space $\mathcal{B}=\mathcal{PC}_{r} \times L^{p}(h,H)$ satisfies axioms (A)--(C). Moreover, when $r=0 $ and $p =2$, we can take $\tilde{H}=1$, $M(t)=\gamma(-t)^{1/2}$ and $K(t)=1+(\int_{-t}^{0}h(\tau)d\tau)^{1/2}$, for $t \geq0$ (see \cite[Theorem 1.3.8]{h4} for details). Additionally, we will assume that \begin{itemize} \item[(i)] The functions $\rho_i:[0,\infty)\to [0,\infty),i=1,2$, are continuous. \item[(ii)] The functions $\mu_1 : \mathbb{R} \to\mathbb{R}$, are continuous, and $l_1=(\int_{-\infty}^0\frac{(\mu_1(s))^2}{h(s)}ds)^{1/2}<\infty$. \item[(iii)] The function $\mu_2 : \mathbb{R}^{4} \to\mathbb{R}$ is continuous and there exist continuous functions $b_1,b_2:\mathbb{R} \to\mathbb{R}$ such that $$ |\mu_2(t,s,x,y)|\leq b_1(t)b_2(s)|y|, \quad (t, s, x,y) \in \mathbb{R}^{4} $$ with $l_2=(\int_{-\infty}^0\frac{(b_2(s))^2}{h(s)}ds)^{1/2}<\infty$. \item[(iv)] The functions $\eta_k : \mathbb{R} \to\mathbb{R},k=1,2,\dots,m $, are continuous, and $L_k=(\int_{-\infty}^0\frac{(\eta_k(s))^2}{h(s)}ds)^{1/2}<\infty$ for every $k=1,2,\dots,m$. \end{itemize} In the sequel, $\mathcal{B}$ will be the phase space $\mathcal{PC}_0 \times L^2(h,H)$. Set $\varphi(\theta)(x)=\varphi(\theta,x)\in \mathcal{B}$, defining the maps $G:[0,b]\times \mathcal{B}\to H $, $ F:[0,b]\times \mathcal{B}\to \mathcal{P}(H) $ by \begin{gather*} G(t,\varphi)(x)=\int_{-\infty}^0\mu_1(\theta)\varphi(\theta)(x)d\theta,\\ D(t,\varphi)(x)=\varphi(0)x+G(t,\varphi)(x), \quad J_t^{\alpha-1}G(t)=\int_0^{t}\frac{(t-s)^{\alpha-2}}{\Gamma(\alpha-1)}G(s)ds, \\ F(t,\varphi)(x)=\int_{-\infty}^0\mu_2(t,\theta,x, \varphi(\theta))(x) d\theta, \quad \rho(t,\varphi)=\rho_1(t)\rho_2(\| \varphi(0)\|). \end{gather*} From these definitions, it follows that $G,F $ are bounded linear operators on $\mathcal{B}$ with $\| G\|\leq L_{G}$ and $\| F\|\leq L_{F},\| I_k\|\leq L_k$, $k=1,2,\dots,m$, where $L_{G}=l_1,L_{F}=\| b_1\|_{\infty}l_2$. Then the problem \eqref{e4.1}-\eqref{e4.4} can be written as system \eqref{e1.1}-\eqref{e1.3}. Further, we can impose some suitable conditions on the above-defined functions to verify the assumptions on Theorem \ref{thm3.1}, we can conclude that system \eqref{e4.1}-\eqref{e4.4} has at least one mild solution on $[0,b]$. \subsection*{Conclusion} We have studied the existence of mild solutions for a class of impulsive fractional partial neutral stochastic integro-differential inclusions with state-dependent delay and solution operator, which is new and allow us to develop the existence of various partial fractional integro-differential inclusions and partial stochastic integro-differential inclusions. An application is provided to illustrate the applicability of the new result. 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