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Heart failure is the final pathway for a wide spectrum of myocardial stress, including hypertension and myocardial infarction. However, the potential effects of metformin on cardiac hypertrophy are still unclear.

This paper is concerned with L2-gain disturbance attenuation problem for linear multivariable systems. First, high gain output feedback theorem for L2-gain disturbance attenuation is obtained in case of minimum phase system. Next, we consider L2-gain disturbance attenuation problem for general (nonminimum phase) systems. As a control law, P·SPR·D and/or P·SPR·D+I control is applied (SPR is an abbreviation for strict positive real). We can solve the problem by changing the general system to minimum phase one with the use of P, SPR, D elements and by applying the above high gain output feedback theorem.

This paper is concerned with controlling chaos. Lorenz model, a well known chaotic system, is picked up as a controlled plant in which manipulated variables are additive control inputs. For a controlling technique, we apply a method called the direct gradient descent control(DGDC), which is a dynamic state feedback controller for general nonlinear systems. DGDC manipulates control inputs directly so as to decrease a performance function like the squared error, based on the gradients of the performance function and the steepest descent method. Several simulation results demonstrate the usefulness of the proposed method for the Lorenz chaotic system.

This paper is concerned with derivation and tuning of PID control law. In the first half, output tracking for general nonlinear system is investigated by means of direct gradient descent control (DGDC). In the second half, PID control law for linear systems is derived by using the output tracking DGDC, and at the same time best tuning of PID controller parameters is established. Simulation studies for various plants showed remarkably good performance.

This paper is concerned with tracking control of nonlinear multivariable systems whose relative degree is more than one. The control method is based on a direct steepest descent method using the gradient of a performance index such as the squared error from a desired equilibrium. Several simulation results demonstrate the usefulness of the proposed method.

We study optimization methods for systems with plural objective functions. First, several algorithms for the unique solution to multiple objective programs are proposed by introducing concept of satisfaction conditions and preference ordering among objective functions. The resulting solutions satisfy Pareto optimality. Second, an optimization problem for a decentralized hierarchical system is formulated such that local systems have their own, independent objectives within some restrictions imposed by a central system. The central system governs local ones by means of resource allocation and optimizes its own objective by suitably allocating resources to them, and each local system optimized its own objective consuming the given resources. Finally, relation between Pareto optimality and decentralized hierarchical optimization is discussed.

Necessary conditions for optimal control problems with state-control variable inequality constraints are obtained via mathematical programming formulation and functional analysis in Banach space. These conditions are general ones that hold without any constraint qualifications but differentiability. Furthermore, these conditions are shown to be equivalent to the classical result in the presence of the linear independence constraint qualification.

This paper is concerned with a design method for optimizing dynamic compensators of Pearson’s type. Optimal parameter matrices are obtained by use of a parameter matching technique and an arbitrary pole placement technique. The controlled system has the optimal LQ modes and the modes with arbitrarily quick damping. The presented compensator works as the optimal regulator with observer and performs about the same control as the optimal regulator. And it is designed not in two steps; observer, regulator, but in one step; optimization of output feedback gain without considering any state estimation.

This paper concerns a group decision problem for competitive system where plural decision-makers exist. The group must choose the alternative that is “best for the group” in some sense. The problem is formulated as follows. Each decision-maker is guaranteed with the satisfaction condition such that his objective function should be always kept below a certain permissible level, regardless of whatever opponents’ decisions may be taken. All decision-makers then cooperate together and seek a group preference solution to minimize a group’s objective function under the satisfaction condition. Hence a two-level optimization problem whose constraints include maximizations by the opponents is presented.

This paper concerns a static multi-objective control problem of the distributed parameter system, in which regionally decentralized plural decision-makers carry out control actions based on their own goals. The problem is formulated as minimization of vector functional to generate noninferior controls. Optimality conditions are derived. Moreover, we study a multi-objective decision problem to choose a preference optimal solution from among a set of non-inferior controls. We consider the following two cases; a) there exists a central decision-maker in the upper level (a central decision problem), and b) no central decision-maker exists and a collective decision is made (a collective decision problem). Two-level computational procedures using a constrained simplex method and an interior penalty method are presented for both cases. Gradient method is used for optimizing a system governed by partial differential equations.

This paper is concerned with a design method for optimizing dynamic compensators of Pearson’s type. Optimal parameter matrices are obtained by use of a parameter matching technique and an arbitrary pole placement technique. The controlled system has the optimal LQ modes and the modes with arbitrarily quick damping. The presented compensator works as the optimal regulator with observer and performs about the same control as the optimal regulator. And it is designed not in two steps; observer, regulator, but in one step; optimization of output feedback gain without considering any state estimation.

In this paper we review recent investigations of nucleon-nucleon and hyperon-nucleon interactions employing a non-relativistic quark cluster model. We concentrate mainly on the short and medium-range behavior of the baryon-baryon interaction based on the one-gluon and meson exchange potentials. The chiral quark model based on pion and sigma exchange between quarks is also discussed. We also review a study of the deuteron and its electromagnetic properties in a quark model with exchange currents.

The quark cluster model of the baryon-baryon interaction is reviewed. The emphasis is on the foundation of the approach and the main features of the model. The origins of the short-range repulsion in the nuclear force and other baryonic interactions are discussed.

The quark cluster model studies concerning the H dibaryon are reviewed. The covered topics are the H dibaryon itself, the interaction between a nucleon and an H dibaryon, and the one between two H dibaryons. A related study on the H dibaryon in nuclear matter is also reviewed and its implication to double hypernuclei is discussed.

The quark cluster model of the baryon-baryon interaction is reviewed. The emphasis is on the foundation of the approach and the main features of the model. The origins of the short-range repulsion in the nuclear force and other baryonic interactions are discussed.

The quark cluster model studies concerning the H dibaryon are reviewed. The covered topics are the H dibaryon itself, the interaction between a nucleon and an H dibaryon, and the one between two H dibaryons. A related study on the H dibaryon in nuclear matter is also reviewed and its implication to double hypernuclei is discussed.

In this paper we review recent investigations of nucleon-nucleon and hyperon-nucleon interactions employing a non-relativistic quark cluster model. We concentrate mainly on the short and medium-range behavior of the baryon-baryon interaction based on the one-gluon and meson exchange potentials. The chiral quark model based on pion and sigma exchange between quarks is also discussed. We also review a study of the deuteron and its electromagnetic properties in a quark model with exchange currents.