This paper proposes a new model for state-dependent delay systems, which arise in various fields. After discretization and state augmentation to include the past history, the delay term is represented by using a nonlinear gain whose element is a piecewise linear function of the state. Thus the model becomes nonlinear but finite dimensional. The SOS (Some Of Squares) technique is then applied to analyze stability of this system. Numerical simulation is carried out to illustrate the effectiveness of the proposed method.
Accurate control of quantum spin is necessary in order to utilize quantum spin as the physical realization of the quantum bit. Feedback control (based on continuous quantum measurement) of quantum spin systems inevitably suffers from estimation delays. In this paper, we state that a control system which takes into account these delays can be described by using stochastic delay differential systems. Moreover, we can restrict our analysis to the class of systems which have polynomial coefficients and evolve in a bounded semi-algebraic set. Then, the problem of stabilizing such systems is shown to be solvable effectively via reduction to a semi-algebraic problem.
In this paper, tone color analysis problem is actually studied based on the data rated by the semantic differential technique and points out that a semantic inconsistent correlation may be caused if the conventional method transforms the data of the ordinal scale into the interval one in order to calculate the correlation. The conventional method using the correlation information sometimes causes analytical ill results called Heywood case. Then, this paper studies the rating process and proposes a new association and factor analysis method not using the correlation information. The validity and usefulness of the proposed method, and the difference between the proposed one and the conventional one are shown and discussed by comparing both of the concretely proceeded results.
Characteristics of a Redox Flow (RF) battery are discussed for the transient state near practical operating setups. The RF battery has an ability of high-speed response. However, the transient characteristics have not been clearly understood because of the conjugated system structure in electric circuits, chemical reactions, and liquid flow dynamics. This research aims to serve the design of the charge/discharge cell and the optimization of the control for the dynamic operation of RF batteries.