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A static electricity is useful energy, but it becomes a source of the malfunction or failure of electronic device. This type of the electrostatic problem cannot be ignored. An electronic device in a metal case of a box causes easily not only an error but also failure by the induced voltage of less than 10 V level. The voltage of a charged human body handling the electronic device exceeds occasionally 10 kV level. When the charged human body operates the electronic device by a charged hand, the high induced voltage is generated in the metal case. In the experimental study, the induced voltage is measured using a real experimental setup when the charged object moves away from a partly opened metal case to the direction of the left or the right or the back. The measurement of the induced voltage in the metal case is performed using a spark gap and an electromagnetic wave sensor. The results show the induced voltages in the metal case are −0.6 times of the voltage of a charged object when the charged object moves away from the metal box. The results will be helpful to solve the malfunction or failure of the electronic device caused by the induced voltage.

Multi-Agent Systems (MAS) is made up of multiple autonomous agents. The overall behavior of MAS is determined by local interactions between agents. In the MAS control theory, attention has recently been focused on approaches considering network structure based on the graph theory. In this study, we look at the consensus problem of MAS under communication limitations. In particular, we propose Funnel Control as a new control method to achieve consensus. Funnel Control is a method of high gain adaptive control that can guarantee tracking with a preset degree of accuracy. We perform a simulation study, and demonstrate the effectiveness of Funnel Control for the MAS consensus problem, considering communication limitations.

We developed an upper limb motion assist device for high cervical spinal cord injury. This device consists of an upper-limb motion-assist mechanism, a control system and a sensor. The upper limb motion assist mechanism has a spring and 4 DC motors. The upper limb is always supported in various postures by the same force as gravity exerts due to the elastic force of the spring. The device can be adjusted for upper limbs of different weight. The three-dimensional position of the wrist and the pronosupination motion are assisted by 4 DC motors controlled by a PC. For self-motion control, an acceleration sensor and switches are applied to measure the head motion. This device can assist with upper-limb motions, such as those required to eat independently in response to the head movements of the user.

This paper proposes a design and implementation of an MPI-IO implementation of the Gfarm file system, called MPI-IO/Gfarm. The Gfarm file system is a global file system that federates the local storage of compute nodes among several clusters. It has a scale-out architecture designed to support distributed data-intensive computing. However Gfarm file system does not achieve scalable performance in the case of parallel writes to a single file, a typical file operation in MPI-IO. This paper proposes an optimization technique to improve the parallel write performance to a single file. In the evaluation, MPI-IO/Gfarm achieves scalable parallel I/O performance.

Due to its ability to provide requested resources on demand, the use of cloud computing for data-intensive computing is expected to skyrocket in the coming years. The present IaaS cloud infrastructure is designed such that the compute cloud and the storage cloud are separate components. However, the design has one major problem, namely a trade-off has to be made between the network cost and storage performance. To cope with these problems, we are proposing high performance file system service in compute cloud that transparently utilizes file access locality on dynamic configuration of cloud computing infrastructure. We evaluated the system using micro benchmarks, MapReduce applications, and MPI-IO applications. Our system shows the scalable file I/O performance.

This paper presents a virtual reality-enhanced hand rehabilitation support system with a symmetric master-slave motion assistant for independent rehabilitation therapies. This system consists of a hand exoskeleton device and a lateral symmetric master-slave motion assistant system joined with a virtual reality (VR) environment. Since most disabilities caused by cerebral vascular accidents or bone fractures are hemiplegic, we adopted a symmetric master-slave motion assistant system in which the impaired hand is driven by the healthy hand on the opposite side. Furthermore, a VR environment displaying an enjoyable exercise was introduced. To verify the effectiveness of this system, a clinical trial was executed using one subject.