Junichi Akita

Nonvolatile SRAM based on Phase Change

We propose a novel architecture (phase change nonvolatile SRAM: PNSRAM) combining SRAM with PRAM. This architecture is possible solution to reduce the program cycle at the nonvolatile material to be divided a program sequence into volatile and nonvolatile. In this paper, we describe the PNSRAM architecture and a circuit simulation results of the volatile and nonvolatile operation

Pulse number control of electrical resistance for multi-level storage based on phase change

Phase change nonvolatile memory devices composed of SeSbTe chalcogenide semiconductor thin film were fabricated. The resistivity of the SeSbTe system was investigated to apply to multi-level data storage. The chalcogenide semiconductor acts as a programmable resistor that has a large dynamic range. The resistance of the chalcogenide semiconductor can be set to intermediate resistances between the amorphous and crystalline states using electric pulses of a specified power, and it can be controlled by repetition of the electric pulses. The size of the memory cell used in this work is 200 nm thick with a contact area of 1 µm diameter. The resistance of the chalcogenide semiconductor gradually varies from 41 kΩ to 840 Ω within octal steps. The resistance of the chalcogenide semiconductor decreases with increasing number of applied pulses. The step-down characteristic of the resistance can be explained as the crystalline region of the active phase change region increases with increasing number of applied pulses. The extent of crystallization was also estimated by the overall resistivity of the active region of the memory cell.

RoboCup Jr.: RoboCup for edutainment

The Robot World Cup Initiative (RoboCup) is an international joint project to promote science and technology in intelligent robotics, AI and related fields with the specific goal of building a fully humanoid robot that can be the human world cup champion by 2050, and to apply technologies developed in this activity to socially significant issues such as rescue, and for next generation industries. This idea inspired the imagination of people and it has grown to be one of the largest research areas in multi-agent robotics. The paper discusses extension of RoboCup activity for education and edutainment. Specifically, RoboCup has initiated a new project called RoboCup Jr. that aims at promotion of engineering education and popularization of robotics using RoboCup. A RoboCup Jr. league will be created to meet diverse needs of the education field, and a series of organizational frameworks are proposed to develop a network of social, personal, educational, and technical infrastructures to assist those who are interested in RoboCup Jr. activity.

A CMOS image sensor with pseudorandom pixel placement for clear imaging

The picture element (pixel) in conventional image sensors, such as CCD or CMOS imager, are placed in the form of a lattice for ease of implementation. Lattice placement of pixels intrinsically has directional dependency on the clarity of image representation; in other words, the image clarity is significantly dependent on the directions of the objects in the image, such as lines. For example, horizontal lines are perfectly represented by lattice pixels, while slanted lines have jagged edges. In this paper, we propose a pseudorandom pixel placement architecture for clear imaging with solving the directional dependency problems. We also discuss our evaluation of its characteristics based on the designed layout of CMOS image sensor with pseudorandom pixel placement, as well as its implementation.

Detection of Muscle Fatigue by the Surface Electromyogram and Its Application

The muscle is moved by muscle fiber contraction receiving command from the brain. But, energy that moves muscle is not infinity. If muscle get into energy shortage, no matter how send command from the brain, muscle is not moved. Such a temporary muscular dysfunction is muscle fatigue. If muscle becomes excess fatigue condition, it may decrease work efficiency, or muscle strain. If we are able to measure muscle fatigue objectively, improve work efficiency, or avert muscle strain. Therefore, it is necessity to measure muscle fatigue. It is able to objectively measure with a surface electromyogram (EMG). The feature of muscle fatigue are increase in amplitude and make the transition from high frequency spectrum to low frequency spectrum. We evaluate muscle fatigue Mean Power Frequency (MPF). to evaluates frequency of surface EMG. We assume muscle recovery process is converse phenomenon from muscle fatigue, and it is able to evaluate elevated MPF. The purpose of the present study is to design of system that effective training, or improve work efficiency, or avert muscle strain uses feature of muscular fatigue and muscle recovery process.

Finger Motion Classification Using Surface-Electromyogram Signals

The finger movement has the information about force, speed to bend and the combination of fingers. If these information is estimated, the many degrees of freedom interface can apply it. In this study, we aimed for the many degrees of freedom finger movement classification. We tried each fingers classification and the estimate of the flexural finger force using surface-electromyogram signals. In the technique, amount of characteristic are a cepstral coefficient of EMG signals and an integral calculus EMG signals. A support vector machine performs learning and classtification. Therefore, I propose the classification technique and inspected a classification each finger and the combination of fingers by offline data handling using surface EMG signals.

Real-Time Color Detection System Using Custom LSI for High-Speed Machine Vision

The quantity of image information is very large, and this is why it is difficult to process them in real time, such as video frame rate. In this paper we demonstrate the developed real-time color detection system for the vision system of RoboCup Small-Size League. The pixels color information is converted to HSV color system at first, and judged whether it has the color information of target. The detected information is converted to gray scale NTSC signal to be captured by PC, which is faster than the full color frame grabber.

Wearable Biomedical Monitoring System Using TextileNet

We developed and tested a biomedical monitoring system using TextileNet, a flexible conductive garment for wearable computing. TextileNet detects biological signals while simplifying communication and power supply wiring. TextileNet also acts as an electromagnetic interference (EMI) shield, which makes it possible to use simpler amplifiers in the system. Using TextileNet, a huge amount of biological information can be processed simultaneously.

CyARM-interactive device for environment recognition using a non-visual modality

The purpose of this research is to develop an interactive device for environment recognition, which uses senses other than vision. At present there is no interactive device with which a person who is visually handicapped can gain an intuitive impression of the external world. Our device, which we have named CyARM, has a mechanism that controls the motion of a visually impaired person’s arm according to information about distance gathered by an ultrasonic sensor. We refined the features of CyARM through experimentation. The user can identify not only the existence of an object, but also its form.

And the Fans Are Going Wild! SIG plus MIKE

We present an implemented commentary system for realworld robotic soccer. Our system uses an overhead camera to pass game information to the simulator league commentary program MIKE, and uses the humanoid robot SIG to provide a physical embodiment for the commentary. The use of a physical robot allows us to direct audience attention to important events by looking at them, provide more realism to the interaction between MIKE and other humans in the domain, and even set up a dialogue with the audience as part of the commentary itself. Our system combines the multi-modal input of audio and video information to generate a multi-modal commentary that brings the extra dimension of body language to the social interaction that characterises the overall commentary task.