Robust stability conditions obtained through generalization of the notion of energy dissipation in physical systems are discussed in this report. Linear time-invariant (LTI) systems which dissipate energy corresponding to quadratic power functions are characterized in the time-domain and the frequency-domain, in terms of linear matrix inequalities (LMIs) and algebraic Riccati equations (AREs). ...

In this paper, the min-time optimal control problem is mainly investigated in the linear time invariant (LTI) continuous-time control system with a constrained input. A high order dynamical LTI system is firstly considered for this purpose. Then the Pontryagin principle and some necessary optimality conditions have been simultaneously used to solve the optimal control problem. These optimality ...

is obtained as another special case' In this paper, we formulate continuous time linear fractional shift invariant (LFSI) systems that generalize the well-known linear time invariant (LTI) systems by means of an angle parameter 4. LTI systems are obtained as a special case of LFSl systems for 4 = 0. LFSl systems belong to the large class of time-varying systems. Whereas LTI systems commute with...

Both linear time-invariant (LTI) and linear time-varying (LTV) systems are addressed. They are placed in a unified conceptual framework. The characteristic equation for each subclass is formulated as a Riccati equation. Where LTI-systems lead to algebraic Riccati equations, the LTV-case generalizes this result to differential Riccati equations.

For the first time, in this paper, a robust stability test procedure is proposed for linear time-invariant fractional order systems (LTI FOS) of commensurate orders with interval uncertain parameters. For the LTI FOS with no uncertainty, the existing stability test (or check) methods for dynamic systems with integer-orders such as Routh table technique, cannot be directly applied. This is due t...

The formation of lymph nodes is a complex process crucially controlled through triggering of LTbetaR on mesenchymal cells by LTalpha(1)beta(2) expressing lymphoid tissue inducer (LTi) cells. This leads to the induction of chemokines to attract more hematopoietic cells and adhesion molecules to retain them. In this study, we show that the extravasation of the first hematopoietic cells at future ...

Skin conductance responses (SCR) are increasingly analyzed with model-based approaches that assume a linear and time-invariant (LTI) mapping from sudomotor nerve (SN) activity to observed SCR. These LTI assumptions have previously been validated indirectly, by quantifying how much variance in SCR elicited by sensory stimulation is explained under an LTI model. This approach, however, collapses ...

During fetal development, lymphoid tissue inducer cells (LTis) seed the developing lymph node and Peyer's patch anlagen and initiate the formation of both types of lymphoid organs. In the adult, a similar population of cells, termed lymphoid tissue inducer-like cells (LTi-like cells), supports the formation of organized gut-associated lymphoid tissue (GALT) in the intestine, including both isol...

In this paper we consider the servomechanism problem for SISO positive LTI systems. In particular, we solve the robust servomechanism problem of nonnegative constant reference signals for stable SISO positive unknown LTI systems with constant nonnegative unmeasurable disturbances under strictly nonnegative control inputs, using a clamping tuning regulator.