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Hitoshi UMEZAWA Shingo MIYAMOTO Hiroki MATSUDAIRA Hiroaki ISHIZAKA Kwang-Soup SONG Minoru TACHIKI Hiroshi KAWARADA
RF diamond FETs have been realized on a hydrogen-terminated diamond surface conductive layer. By utilizing the self-aligned gate fabrication process which is effective for the reduction of the parasitic resistance, the transconductance of diamond FETs has been greatly improved. Consequently, the high frequency operation of 22 GHz has been realized in 0.2 µ m gate diamond MISFETs with a CaF2 gate insulator. This value is the highest in diamond FETs and is comparable to the maximum value of SiC MESFETs at present.
Kiyomi NAKAMURA Shingo MIYAMOTO
Although previous studies using artificial neural networks have been actively applied to object shape recognition, little attention has been paid to the recognition of spatial elements (e.g. position, rotation and size). In the present study, a rotation and size spreading associative neural network (RS-SAN net) is proposed and the efficacy of the RS-SAN net in object orientation (rotation), size and shape recognition is shown. The RS-SAN net pays attention to the fact that the spatial recognition system in the brain (parietal cortex) is involved in both the spatial (e.g. position, rotation and size) and shape recognition of an object. The RS-SAN net uses spatial spreading by spreading layers, generalized inverse learning and population vector methods for the recognition of the object. The information of the object orientation and size is spread by double spreading layers which have similar tuning characteristics to spatial discrimination neurons (e.g. axis orientation neurons and size discrimination neurons) in the parietal cortex. The RS-SAN net simultaneously recognizes the size of the object irrespective of its orientation and shape, the orientation irrespective of its size and shape, and the shape irrespective of its size and orientation.
Shingo MIYAMOTO Hideki TODE Koso MURAKAMI
The block-based fast transmission scheme, which is one of typical stored video delivery schemes, is reasonable in terms of its bandwidth efficiency and tolerance to the delay jitter, etc. However, it causes packet loss because of its burst data transmission method. Thus, we propose a slotted multicast scheme for MPEG video based on the block transmission scheme to maintain a higher quality and to include time constraints. We define two delivery units, the "GoPs Group" and the "Frame Type," on the basis of the MPEG characteristics with periodical NACK feedback from the clients. The former is tolerant to burst packet loss, and the latter gives priority to important frames. Our block multicast has two phases: a "Transmission Phase" and a "Retransmission Phase." In the former, a server multicasts a block, and in the latter, a server retransmits lost packets using multicast according to the proper delivery unit. We evaluate our proposal from some viewpoints with a computer simulation. We also measure the quality of the video reflected the result of a computer simulation. From these results, we confirm performance effectiveness of our proposal.
Morgan Hirosuke MIKI Mamoru SAKAMOTO Shingo MIYAMOTO Yoshinori TAKEUCHI Toyohiko YOSHIDA Isao SHIRAKAWA
This paper evaluates the code efficiency of the ARM, Java, and x86 instruction sets by compiling the SPEC CPU95/CPU2000/JVM98 and CaffeineMark benchmarks, from the aspects of code sizes, basic block sizes, instruction distributions, and average instruction lengths. As a result, mainly because (i) the Java architecture is a stack machine, (ii) there are only four local variables which can be accessed by a 1-byte instruction, and (iii) additional instructions are provided for the network security, the code efficiency of Java turns out to be inferior to that of ARM Thumb. Moreover, through this efficiency analysis it should be stressed that there exists the high potential of constructing a more efficient code architecture by taking minute account of the customization of an instruction set as well as the number of registers.