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A theoretical investigation of neutral-type of delayed inertial neural networks using the Lyapunov stability theory and Linear Matrix Inequality (LMI) approach is presented. Based on a suitable variable transformation, an inertial neural network consisting of second-order differential equations can be converted into a first-order differential model. The sufficient conditions of the delayed inertial neural network are derived by constructing suitable Lyapunov functional candidates, introducing new free weighting matrices, and utilizing the Writinger integral inequality. Through the LMI solution, we analyse the global asymptotic stability condition of the resulting delayed inertial neural network. Simulation examples are presented to demonstrate the effectiveness of the derived analytical results. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a hybrid neural network model, based on the integration of fuzzy ARTMAP (FAM) and the rectangular basis function network (RecBFN), which is capable of learning and revealing fuzzy rules is proposed. The hybrid network is able to classify data samples incrementally and, at the same time, to extract rules directly from the network weights for justifying its predictions. With regards to process systems engineering, the proposed network is applied to a fault detection and diagnosis task in a power generation station. Specifically, the efficiency of the network in monitoring the operating conditions of a circulating water (CW) system is evaluated by using a set of real sensor measurements collected from the power station. The rules extracted are analyzed, discussed, and compared with those from a rule extraction method of FAM. From the comparison results, it is observed that the proposed network is able to extract more meaningful rules with a lower degree of rule redundancy and higher interpretability within the neural network framework. The extracted rules are also in agreement with experts’ opinions for maintaining the CW system in the power generation plant. [Copyright &y& Elsevier]

Segmentation is the process of extraction of objects from an image. This paper proposes a new algorithm to construct intuitionistic fuzzy set (IFS) from multiple fuzzy sets as an application to image segmentation. Hesitation degree in IFS is formulated as the degree of ignorance (due to the lack of knowledge) to determine whether the chosen membership function is best for image segmentation. By minimizing entropy of IFS generated from various fuzzy sets, an image is thresholded. Experimental results are provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a hybrid Artificial Neural Network (ANN) model that is developed for noisy data classification. The model, named GRNNFA, is a fusion of the Fuzzy Adaptive Resonance Theory (FA) model and the General Regression Neural Network (GRNN) model. The GRNNFA model not only retains the important features of the parent models, which include stable learning, fast training, and an incremental growth network structure, but also facilitates the removal of noise that is embedded in training samples. The robustness of the GRNNFA model is demonstrated by the Noisy Two Intertwined Spirals problem and other benchmarking problems. The model is then applied to Fisher''s Iris Data, which is a real-world classification problem. The results show that the percentage of correct predictions is statistically higher than in variant models of the adaptive resonance theory. The GRNNFA is further employed in a new application area of soft computing—fire dynamics, which is highly non-linear in nature. Flashover is the most dangerous scenrio in the development of a compartment fire, during which, any unburned combustible material, including the unburned soot particles inside the compartment, is ignited spontaneously and all combustible material is then simultaneously involved in the burning process. The GRNNFA model is applied to predict the occurrence of the flashover in compartment fires based on the fire size and the geometry of the fire compartment. The performance of the GRNNFA is compared with other published results, and it is shown to be statistically superior to other ANN models. [Copyright &y& Elsevier]

This article, we explore the asymptotic stability and asymptotic synchronization analysis of fractional order delayed Cohen–Grossberg neural networks with discontinuous neuron activation functions (FCGNNDDs). First, under the framework of Filippov theory and differential inclusion theoretical analysis, the global existence of Filippov solution for FCGNNDDs is studied by means of the given growth condition. Second, by virtue of suitable Lyapunov functional, Young inequality and comparison theorem for fractional order delayed linear system, some global asymptotic stability conditions for such system is derived by limiting discontinuous neuron activations. Third, the global asymptotic synchronization condition for FCGNNDDs is obtained based on the pinning control. At last, two numerical simulations are given to verify the theoretical findings. [ABSTRACT FROM AUTHOR]

This study is concerned with the problem of leakage-delay-dependent stability analysis of Markovian jumping linear systems with time-varying delays and nonlinear perturbations. Mixed time-varying delays, which include leakage, discrete, and distributed delays, pertaining to the proposed system are addressed. Based on an improved Lyapunov–Krasovskii functional with triple integral terms and by employing the model transformation technique and the reciprocal convex method, the sufficient conditions for the delay-dependent stability of the considered system are derived. Moreover, the sufficient conditions obtained are formulated in terms of linear matrix inequalities to achieve the global asymptotical stability in mean square of the considered delayed system. Finally, numerical examples are provided to demonstrate the less conservatism and effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

• this is the first study, on the global asymptotic stability of Clifford valued NNs with impulsive effects. • the results of our study are more general and newer as compared with those in the literature, even when our considered model degenerates into real-valued, complex-valued, or quaternion-valued systems. • Compared with the related literature, the conditions we need are easy to satisfy and the method used in this study can be easily applied for analyzing other dynamic properties of different delayed Clifford-valued NN models. In this paper, we focus on the global asymptotic stability problem for Clifford-valued neural network models with time-varying delays as well as impulsive effects. By considering impulsive effects, a general class of network model is considered, which encompasses real-valued, complex-valued, and quaternion-valued neural network models as special cases. Firstly, the n -dimensional Clifford-valued model is decomposed into 2 m n -dimensional real-valued model, which avoids non-commutativity of multiplication of Clifford numbers. Based on the Lyapunov stability theory, contraction mapping principle, and some mathematical concepts, we derive the existence, uniqueness of the equilibrium point with respect to the model. New sufficient conditions are also derived, in order to ensure the global asymptotic stability of the considered model. To illustrate the usefulness of the obtained results, a simulation example is presented. [ABSTRACT FROM AUTHOR]

• In light of the comments and suggestions, we have revised the paper very carefully, and ad- dressed all the points raised by the reviewers. We hope this version can be accepted to be published in Applied Mathematics and Computations. Here are some of the highlights. In this revision, our contribution mainly falls in the application part for the considered model. Firstly, we have created a mathematical model that describes an interaction between wild mosquitoes and wolbachia infected mosquitoes. Then we tried to linearize the model and get a positive system. In order to solve and find the system stability results for our mathematical model firstly, we have constructed a delayed positive system and then extended them into delayed positive system with uncertain control. While construction, we face more difficulties in finding an appropriate approach to solve the addressed mathematical model. And also in numerical examples of application part we have 6 × 6 matrices and hence it is difficult to obtain the random values in which the system stable. Finally, to prove our model is stable by this approach, we have to show that Ω + Ω μ K + Ω μ Δ K (t) is a metzler matrix. To get this we have to adjust the gain matrix K and the uncertain matrix Δ K (t). Further the construction of Lyapunov function for this model is very strenuous. • Finally, we would like to take this opportunity to thank the editor and the reviewers again for their constructive comments and useful suggestions, and the time and efforts that they have spent in the review process. Without the expert comments made by the editor and the reviewers, the paper would not be of this quality. This note pays precise attention to derive the γ -exponential stability results of positive delayed systems via non-fragile control. By using Lyapunov–Krasovskii theory some necessary conditions are derived. Moreover, by using results from spectrum analysis the sufficient conditions for positive delayed systems with non-fragile control are analyzed. Our main intension is to locate the ideal application of this type of systems. In later part of this paper, the novel mathematical model which describes the life stages of Aedes Aegypti mosquitoes is proposed. In that model, the life shorting bacteria called Wolbachia is used as a biological control. By moderately thinking about the uncertain conditions in the biological control we implemented the non-fragile control. By applying the proposed results the γ -exponential stability of this population system is derived. Finally, some numerical examples are provided to expose the effectiveness of our predominant results. [ABSTRACT FROM AUTHOR]

Purpose Left Ventricular Assist Device (LVAD) has become the standard of care for many patients with advanced heart failure awaiting cardiac transplant. However, due to the lack of available donor hearts in Singapore, the length of time on LVAD support as a Bridge to Transplant (BTT) therapy has increased over the years. Methods A single-center, retrospective review of consecutive patients undergoing LVAD implantation between May 2009 and October 2017. Results Sixty-five patients (82% male) had LVAD implanted as BTT therapy. Mean age was 45 ± 11years old. Main heart failure etiologies were dilated cardiomyopathy (45%) and ischemic cardiomyopathy (39%). 39% were INTERMACS 1, 13% INTERMACS 2, 39% INTERMACS 3 and 8% INTERMACS 4. LVADs implanted included 55% HeartMate II, 31% HeartWare HVAD and 14% HeartMate 3.Median duration of post-operative hospitalization and intensive care stay were 29 (range 9 to 130) and 7 (range 3 to 122) days respectively. Four patients (6%) had right ventricular failure leading to right VAD placement post-operatively. Other early postoperative complications included infections (61%), gastrointestinal bleeding (19%), stroke (6%) and cardiac tamponade (3%). Haemodialysis was instituted in28%.Median duration of device support was 805 (range 9 to 3102) days. Late complications, expressed in events per patient year, included driveline infection (0.99+/-1.42), pump pocket infection (0.03+/-0.15), pump thrombosis (0.20+/-1.01), stroke (0.19+/-0.81), and gastrointestinal bleeding (0.42+/-1.31). 8% underwent aortic valve closure for late-onset severe aortic regurgitation while 8 (13%) patients underwent pump exchange surgeries.Five-year survival was 89.2%. Twenty-one patients (33%) successfully received cardiac transplantation. Median wait to heart transplant was 893days (range 62 to 1685 days). Myocardial recovery was achieved in two patients (3%). Conclusion Due to the scarcity of cardiac transplants, many patients remain on LVAD support for an extended period. This has resulted in an increased incidence of complications while awaiting a suitable donor. [ABSTRACT FROM AUTHOR]

Purpose Patients with advanced heart failure often have significant mitral valve regurgitation (MR).The Alfieri stich mitral valve repair (AsMVR) can be performed during LVAD implantation with negligible additional surgical time. We report our experience on concomitant AsMVR during LVAD surgery. Methods A single-centre retrospective analysis of patients receiving LVADs between May 2009 to November 2017. Patients with moderate to severe MR were included. Patients who underwent mitral annuloplasty were excluded. MR was scored according to severity: No MR = 0; Trivial MR = 1, Mild MR = 2; Moderate MR = 3; Severe MR = 4. Safety and efficacy outcomes of patients who underwent AsMVR were compared against patients who did not. Results Ninety patients were included. 53 patients had at least moderate MR. Eleven underwent AsMVR. Pre-operatively, there was no difference in mean MR grade (3.45±0.47 vs 3.37±0.42, p=0.58), mean pulmonary artery pressure (mPAP) (46±17 vs 46±6, p=0.93) and pulmonary artery wedge pressure (PAWP) (33±12 vs 34±6, p=0.66) between the AsMVR and the non-AsMVR groups. Three months after LVAD implantation, there was no difference in mean MR grade between the AsMVR and no-AsMVR groups (2.05±0.76 vs 1.71±-0.92, P=0.3). mPAP (25±6 vs 24±9, p=0.85) and PAWP (14±6 vs 15±9, p=0.68) at 6 months were also not different. Mean transmitral pressure gradient was 2.1± 1.3 mmHg after AsMVR. Seven patients had mitral valve prolapse after AsMVR. There was no mortality at 30-days in the AsMVR group. Conclusion Alfieri stitch mitral valve repair can be safely performed during LVAD surgery. However, it does not appear to reduce mitral regurgitation nor pulmonary artery pressure beyond what the LVAD does. [ABSTRACT FROM AUTHOR]