[in Japanese]

View full abstract

[in Japanese]

View full abstract

We investigate optimal control design of a planar variable geometry truss. Due to high redundancy of the system, we need some systematic optimal trajectory design of generating a motion of the whole system for a required tip motion. Then, we shall propose an algorithm of optimal trajectory design based on inverse kinematics and dynamics. Lastly, we shall illustrate numerical results in simulation.

View full abstract

It is known that when designing active mass dampers for a structure system, the stroke limits of the actuators are major constraints in improving the control performance. We develop a design method of a saturating control law that can effectively attenuate the vibration of a structure system under stroke limits of actuators. Simulation results are shown to demonstrate the effectiveness of the proposed method.

View full abstract

[in Japanese]

View full abstract

We consider stability analysis and design problem for switched descriptor systems under certain commutation condition, and establish the condition for stability under arbitrary switching and stabilizability under a class of switching laws.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

A design and control systems for servo systems is presented. In this system, the controller is designed using LMI tool in Matlab and the maximal admissible sets (MASs) corresponding to reference signals are computed using BB (Beneath Beyond) method which is coded using C++. To switch reference signals by the reference governor, a MAS, which includes the current state, must be determined on line and this is done using BB method.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

We studied the Bilinear Matrix Eigenvalue Optimization because it is very useful for control system design problems. However performance improvement of the algorithm is needed, because of huge amount of computing time is necessary to solve problems. So we parallelize Branch and Bound method with Master-Worker paradigm and implement the algorithm in c++ language. And check the performance of the parallelized algorithm on Beowulf cluster system.

View full abstract

A stochastic ellipsoid method is proposed for a class of robust feasibility problems defined by a set of parameter-dependent convex constraints.In particular, a new update rule is presented for constructing a smaller ellipsoid which contains the intersection of the previous ellipsoid and strips determined by given multiple gradients, which leads to reduction of the total number of random samples necessary for convergence.

View full abstract

[in Japanese]

View full abstract

This paper considers a decentralized anti-windup control synthesis problem based on the generalized sector approach. When the quadratic Lyapunov matrix is set to be a block diagonal one subject to input-output channels of the plant and a desired order of the controller, it is indicated that the sufficient solvability condition can be recast as a linear matrix inequality (LMI) one.

View full abstract

A planar cell-complex is a 2-dimensional cell-complex which can be drawn on a planar surface.If a given planar cell-complex can be drawn on a 2-dimensional space $\mathbb{X}$ under a givn \lq flow-condition $F$\ q,we say the cell-complex has a $(F,\mathbb{X})$-realization.In this paper we show an algorithm to solve the problem of $(F,\mathbb{X})$-realizations.

View full abstract

A planar cell-complex is a 2-dimensional cell-complex which can be drawn on a planar surface. The inverse problem of planar cell-complexes is a problem of enumerating all planar cell-complexes when the number of the 0-cells, 1-cells and 2-cells of the cell-complex is given for us. In this paper we show an algorithm to solve this problem.

View full abstract

In modeling of complex mechanical systems and physical systems, the idea of interconnections has played an essential role. Recently, it has been clarified that such interconnections can be represented by Dirac structures and also be incorporated into associated implicit Hamiltonian systems. In the paper, we shall illustrate how Dirac structures are related with Lagrangian systems, especially, in the context of implicit Lagrangian systems.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

An analysis of spatio-temporal pattern created by self-organization is one of important problems in complex systems. Focusing on chemotactic bacterial colony patterns, the colony formation processes are analyzed. Taking the fluctuation such as impurities in chemical substance into consideration, the influence of the fluctuation on the bacterial colony formations is studied by numerical simulations.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

In this paper, we study supervisory control of concurrent discrete event systems under the assumption that both the plant and the specification are modeled by concurrent synchronous products. We show that, under this assumption, the specification language is always concurrently well-posed, and the controllability alone is a necessary and sufficient condition for the existence of a supervisor.

View full abstract

[in Japanese]

View full abstract

In this paper, we study online supervisory control of discrete event systems with the unknown observable event set. We show that by using a conservative approximation of the unknown observable event set in the online supervisor synthesis procedure proposed by Prosser et al., a supervisor that does not violate a specification can be synthesized without exact knowledge of the observable event set.

View full abstract

[in Japanese]

View full abstract

This paper proposes an aeration control method for advanced wastewater treatment processes for reduction of operational and maintenance costs. A dissolved oxygen meter and ASM1 (Activated Sludge Model No.1) suggested by IWA (International Water Association) are utilized in the method. The simulation results show the effectiveness of the proposed method.

View full abstract

The purpose of this paper is to investigate the modeling and control of a parallel-structured single-link flexible manipulator which can hold heavy load mass. Its dynamics are derived using the Hamilton's principle. In this paper, the exact dynamics of the parallel-structured single-link flexible manipulator is approximated by the dynamics of the flexible arm consisting of a beam for simplicity. An observer and an LQ controller are constructed.

View full abstract

In the previuos paper, we gave a design method of the controller such that level speed of a helicopter follows a step reference. In this paper, we examine thecharacter for the case that virtical speed follows a step reference.

View full abstract

This paper proposes a method of control of an electric shaking table subjected to unknown reaction force caused by motion of the structural model. In order to achieve highly precise control of the table, we have developed an estimation algorithm of the reaction force and a compensator to reduce its effect to the motion of the table which is used with an LQ cotrol.

View full abstract

This paper proposes an identification method using SOS optimization for continuous-time gray-box models with a small number of data and shows the effectiveness using some numerical examples.

View full abstract

[in Japanese]

View full abstract

In this paper, we consider a simultaneous structure/controller design problem of flexible space structures. In particular, we consider optimal placement of sensors and actuators together with control design. Even though this problem is originally non-convex, we transform it into a convex one via a novel approach.

View full abstract

The purpose of this paper is to investigate the LEQG control of Mechanical systems with the optimal risk-sensitive parameter. In this paper, a risk is defined as `deterioration in control performance' and selecting the optimal parameter minimizing the risk. In searching the parameter numerically, the quasi-Newton method is used. (49 words)

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

We will present a protocol of fault tolerant grid migration system using network storage. Our proposed grid migration system has capability to recover from fault in autonomic manner. We also implemented the grid migration system using Globus Toolkit4 and the network storage. Performance evaluation will be reported to show effectiveness of the fault recovery.

View full abstract

[in Japanese]

View full abstract

Recently, NAS with snapshot facility has been focused in the network storage which treats mass data. We present a restart method of recovery using the snapshot. Due to the checkpointing characterized by not only log but also the snapshot, we show performance improvement of our proposal than conventional recovery.

View full abstract

In this paper, we will present a load balance method using data replication. We also show effectiveness of our proposed protocol by its implementation and observation of response time and CPU use ratio based on benchmark test.

View full abstract

We present a coordinated checkpointing using vector timestamp in grid computing. We also evaluate performance to confirm effectiveness of our proposed protocol for the grid computing with scalability.

View full abstract

[in Japanese]

View full abstract

In this paper, high-speed size and orientation invariant eye tracking using template matching and genetic algorithms (GAs) is proposed. Moreover, we try to acquire numerical parameters to represent the eye, for example, position, scaling, and rotation angle. Only one artificial template is used for every human user. We achieved an accuracy of 74% at a processing time of 0.03 seconds.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract