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This article studies the problem of global asymptotic stabilization (GAS) by memoryless state and/or output feedback for a family of nonlinear systems with delays in the state and input. Under a linear growth condition, together with the lower-triangular bounding requirement, it is proved that GAS of the time-delay nonlinear system under consideration is achievable by memoryless state and output feedback, respectively, as long as the input delay is limited. With the aid of the Lyapunov–Krasovskii stability theorem and the feedback domination design approach, we construct, step-by-step, a set of Lyapunov–Krasovskii functionals and memoryless state and/or output feedback controllers, achieving GAS of the closed-loop systems with delays. Extensions to nonlinear systems with inverse dynamics are also included.

This paper studies the problem of global asymptotic stabilization for a class of upper-triangular systems with large delays in the state and input. Using the idea of feedback domination, we develop a Lyapunov-Krasovskii method for the design of time-invariant, memoryless linear state and output feedback controllers, achieving global asymptotic stabilization of the closed-loop systems under a linear growth condition. The resulting controllers are different from predictor-based or delay-dependent controllers in the sense that they are delay-free and easier to be implemented due to the nature of “memoryless” feedback. Two examples are presented to demonstrate the effectiveness of the proposed delay-free state and output feedback control strategies.

This paper considers the problem of output feedback stabilisation for stochastic high-order feedforward nonlinear systems with time-varying delay. By using the homogeneous domination theory and solving several troublesome obstacles in the design and analysis, an output feedback controller is constructed to drive the closed-loop system globally asymptotically stable in probability.

SUMMARY This paper considers the problem of output feedback stabilization for a class of stochastic feedforward nonlinear systems with input and state delay. Under a set of coordinate transformations, we first design a linear output feedback controller for a nominal system. Then, with the aid of feedback domination technique and an appropriate Lyapunov–Krasovskii functional, it is proved that the proposed linear output feedback controller can drive the closed-loop system globally asymptotically stable in probability. Copyright © 2015 John Wiley & Sons, Ltd.

In this paper, the problem of state feedback stabilization for stochastic feedforward nonlinear systems with input time-delay is considered for the first time. By introducing a variable transformation, skillfully combining the homogeneous domination method, and constructing an appropriate Lyapunov-Krasovskii functional, a state feedback controller is developed to guarantee the closed-loop system globally asymptotically stable in probability.

This paper considers the problem of output feedback stabilization of a class of stochastic nonlinear systems with time-varying delay. With the aid of feedback domination technique and the Razumikhin-type theorem, an output feedback controller is designed to drive the closed-loop system globally asymptotically stable in mean square. The main contributions are two folds: 1) Remove the slowly varying assumption on time-varying delay, which is frequently used in dealing with system with time-varying delay. 2) Construct a quadratic Lyapunov function, and present an easy way to deal with Hessian term.

For a class of stochastic high-order nonlinear systems, by introducing the combined homogeneous domination and sign function design approach, this technical note solves the problem of output-feedback control under the weaker high-order and nonlinear growth conditions.

In this paper, a combined homogeneous domination and sign function design approach is presented to state feedback control for a class of stochastic high-order nonlinear systems with time-varying delay. The use of the combined approach relaxes the restriction on nonlinear functions and makes the closed-loop system globally asymptotically stable in probability.

In this paper, we consider the problem of global stabilization for a class of stochastic high-order feedforward nonlinear systems with time-varying delay. By introducing the homogeneous domination design method and constructing the appropriate Lyapunov-Krasovskii functional, a state feedback controller is constructed to drive the closed-loop system to be globally asymptotically stable in probability.

This technical note further investigates more general stochastic nonlinear systems with stochastic integral input-to-state stability (SiISS) inverse dynamics and focuses on solving the following problems: 1) a class of counterexamples which are different from that in are reconstructed to discuss the relationship between two small-gain type conditions on SiISS and 2) under the weaker conditions on nonlinearities, based on a reduced-order observer, small-gain type condition on SiISS and stochastic LaSalle theorem, an output feedback controller is constructed to guarantee the global asymptotical stability in probability of the closed-loop stochastic system.

TACC3, a member of the transforming acidic coiled-coil protein (TACC) family, is a multifunctional protein that is involved in various biological functions, including proliferation and differentiation of tumor cells, cancer progression and metastasis. The aims of the present study were to examine whether TACC3 expression is associated with the proliferation and migration of osteosarcoma (OS) cells and to investigate the potential underlying molecular mechanisms of TACC3 in OS. First, the levels of mRNA and protein expression in OS cell lines by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively were examined. Second, the effects of TACC3 knockdown and overexpression on the proliferative, migratory and invasive capacities of OS cells were investigated. Finally, western blot analysis was employed to detect the potential mechanism of TACC3 in osteosarcoma. TACC3 expression was significantly increased in osteosarcoma tissues and cell lines, compared to matched controls. The knockdown of TACC3 was able to significantly inhibit the proliferation, migration and invasion of osteosarcoma cells, whereas the overexpression of TACC3 was able to promote cell proliferation and migration. Mechanistically, TACC3 may promote the migration and invasion of osteosarcoma cells via through nuclear factor-κB signaling. These data suggest that TACC3 has an important part in the progression of osteosarcoma and may serve as a potential target for gene therapy.

This paper further discusses output-feedback regulation for more general nonlinear systems with integral input-to-state stability (iISS) inverse dynamics and unknown control direction. By using the adaptive backstepping method, an output feedback controller is given to drive the output to the origin while maintaining other closed-loop signals bounded.

This paper further considers more general high-order stochastic nonlinear system driven by noise of unknown covariance and its adaptive state-feedback stabilization problem. A smooth state-feedback controller is designed to guarantee that the origin of the closed-loop system is globally stable in probability.