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Nowadays, with the increased numbers of video cameras, the amount of recorded video is growing. Efficient video browsing and retrieval are critical issues when considering the amount of raw video data to be condensed. Activity-based video synopsis is a popular approach to solving the video condensation problem. However, conventional synopsis methods always consists of complicated and pairwise energy terms that involve a time-consuming optimization problem. In this paper, we propose a simple online video synopsis framework in which the number of collisions of objects is classified first. Different optimization strategies are applied according to different collision situations to maintain a balance among the computational cost, condensation ratio, and collision cost. Secondly, tube-resizing coefficients that are dynamic in different frames are adaptively assigned to a newly generated tube. Therefore, a suitable mapping result can be obtained in order to represent the proper size of the activity in each frame of the synopsis video. The maximum number of activities can be displayed in one frame with minimal collisions. Finally, in order to remove motion anti-facts and improve the visual quality of the condensed video, a smooth term is introduced to constrain the resizing coefficients. Experimental results on extensive videos validate the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

In this brief, many novel theorems and corollaries are presented regarding the global asymptotic stability and global exponential stability of cellular neural networks with constant and variable time delays. The stability conditions in the new results improve and generalize existing ones. Several examples are discussed to compare the new results with the existing ones. Index Terms--Cellular neural networks (CNNs), cloning template, global asymptotic stability, global exponential stability.

This brief studies the global asymptotic stability and the global exponential stability of neural networks with unbounded time-varying delays and with bounded and Lipschitz continuous activation functions. Several sufficient conditions for the global exponential stability and global asymptotic stability of such neural networks are derived. The new results given in the brief extend the existing relevant stability results in the literature to cover more general neural networks. Index Terms--Global asymptotic stability, global exponential stability, neural networks, unbounded time-varying delay(UDNN).

In this paper, we show that any N x M-dimensional delayed cellular neural network described using cloning templates can have no more than [3.sup.NxM] isolated equilibrium points and [2.sup.NXM] of these equilibrium points located in saturation regions are locally exponentially stable. In addition, we give the conditions for the equilibrium points to be locally exponentially stable when the equilibrium points locate the designated saturation region. These conditions improve and extend the existing stability results in the literature. The conditions are also very easy to be verified and can be checked by direct examination of the templates, regardless of the number of cells. Finally, the validity and performance of the results are illustrated by use of two numerical examples. Index Terms--Cellular neural network (CNN), cloning template, isolated equilibria, stability.

This brief presents new theoretical results on the global exponential stability of neural networks with time-varying delays and Lipschitz continuous activation functions. These results include several sufficient conditions for the global exponential stability of general neural networks with time-varying delays and without monotone, bounded, or continuously differentiable activation function. In addition to providing new criteria for neural networks with time-varying delays, these stability conditions also improve upon the existing ones with constant time delays and without time delays. Furthermore, it is convenient to estimate the exponential convergence rates of the neural networks by using the results. Index Terms--Global exponential stability, neural networks, rate of exponential convergence, time-varying delays.

Employing the Razumikhin technique, we present several criteria of input-to-bounded state stabilization and bounded-input-bounded-output stabilization in mean square for nonlinear and quasi-linear stochastic control systems with time-varying delay and time-varying uncertainties. Index Terms--Bounded-input--bounded-output (BIBO) stabilization in mean square, Brownian motion, input-to-bounded state (IBS) stabilization in mean square, Razumikhin technique, stochastic delay system, uncertainty.

Abstract: Dysfunctional adipogenesis such as subcutaneous lipoatrophy is closely related to insulin resistance and metabolic disorders. Although the expression or release of the cytokine interleukin‐1α (IL‐1α) is known to increase in adipose tissue in response to cell death, cell senescence, aging, or solar radiation, the regulatory role of IL‐1α in adipogenesis has not been sufficiently investigated. To investigate the problem, we explored the effect of IL‐1α on the proliferation and adipogenic differentiation of human adipose‐derived mesenchymal stem cells (ADSCs) using cell counting, alamarBlue assay, oil red O staining, Western blot, among others. The results showed that IL‐1α evidently inhibited the proliferation and adipogenic differentiation of ADSCs, which might be related with the activated nuclear factor‐κB (NF‐κB) and extracellular signal‐regulated kinase (ERK) 1/2 pathways. Early‐stage adipogenic differentiation was more sensitive to IL‐1α than late‐stage differentiation. After differentiation of ADSCs into mature adipocytes, adding of IL‐1α had no obvious influence on the cellular morphology, including lipid droplet accumulation. IL‐1α enhanced the expression of proinflammatory cytokines, such as IL‐8, IL‐6, CCL2 (C‐C motif chemokine ligand 2), and IL‐1β, when added into the adipogenic medium of ADSCs. Blocking IL‐8 and IL‐6 with neutralizing antibodies partially alleviated the inhibitory effect of IL‐1α on the proliferation and adipogenic differentiation. The results suggest that IL‐1α inhibits adipogenesis through activation of NF‐κB and ERK1/2 pathways and subsequent upregulation of proinflammatory cytokines in ADSCs. IL‐1α might play an important role in mediating lipoatrophy by regulation of ADSCs. [ABSTRACT FROM AUTHOR]

This paper studies the stability problem of Yang–Chen system. By introducing different radial unbounded Lyapunov functions in different regions, global exponential attractive set of Yang–Chen chaotic system is constructed with geometrical and algebraic methods. Then, simple algebraic sufficient and necessary conditions of global exponential stability, global asymptotic stability, and exponential instability of equilibrium are proposed. And the relevant expression of corresponding parameters for local exponential stability, local asymptotic stability, exponential instability of equilibria are obtained. Furthermore, the branch problem of the system is discussed, some branch expressions are given for the parameters of the system. [ABSTRACT FROM AUTHOR]

The problem of global synchronization control for a class of new Chua's system is studied in this paper. Several linear controllers are proposed to realize the global exponential synchronization of two Chua's systems. Decoupling feedback control method is used to make Chua's system global exponential synchronized. Global exponential synchronization with respect to (w.r.t) partial state variables is studied when one of the error variables is zero. Finally, an adaptive synchronization controller is designed to make the response and the driven systems synchronized. Moreover, the estimate errors of the uncertain parameters converge to zero since the persistent excitation condition holds. Additionally, numerical simulations show the effectiveness of the proposed controllers. [ABSTRACT FROM AUTHOR]