English summary of the third number of volume 42 publishing paper

Original Paper

Title: Search Algorithm for Optimal Roll Tensioning Conditions of Circular Saws
Author: Fumiyasu KURATANI, Tadao YAMANO

題目：丸のこの最適ローラ腰入れ条件の探索法
著者：鞍谷文保・山野惟夫

Abstract

Circular saws are widely used to cut wood. Their transverse vibration in cutting is a serious problem. To improve the dynamic stability of a rotating saw blade, a process called roll-tensioning is performed by which tensile residual stresses are induced within the saw blade with rollers. This paper presents an algorithm for finding the optimal roll tensioning conditions, such as rolling position and rolling load to maximize the lowest frequency of the backward travelling wave of a rotating saw blade. In some examples, the optimal conditions are determined for several rotating speeds of a disk. The results show that the lowest frequency of the backward travelling wave of an optimally tensioned disk increases considerably and the optimal conditions vary with the rotating speed of the disk.

Keywords : Vibration, Optimization Problem, Rotating Disk, Roll-Tensioning, Finite Element Method

Title: Ebullition Behavior of Superheated Water Droplets Washed by Activated Carbon
- The Effect of Washing Conditions -
Author: Michiyoshi SUZUKI, Yasuo HARIGAYA

題目：過熱水滴の突沸挙動に及ぼす供試母液活性炭洗浄条件の影響
著者：鈴木道義・針谷安男

Abstract

Generally, unwettable impurities in water provide an effective site for nucleation. Activated carbon is known as a remover of unwettable minute impurities in water. In this paper the ebullition behavior of water droplets washed by activated carbon was investigated. As a result, it is found that compared with tap water droplets, water droplets washed by activated carbon are apt to boil at a higher degree of superheat, because the unwettable minute impurities in water are selectively removed by the activated carbon.

Key Words : Superheated Water Droplets, Ebullition, Wettability, Impurities, Washing, Activated Carbon

Title: Environmental Learning Support System Constructed by Using Computer Network
Author: Mitsuru TSUKAMOTO, Ryoko KOBAYASHI, Masao TAKEGAWA,Hiroyuki INOUE, Kenji MIYASAKA

題目：ネットワーク上で動作する環境型学習支援システム構築の試み
著者：塚本　充・小林良子・竹川正雄・井上博行・宮阪憲治

Abstract

This paper describes the environmental learning support system constructed by using computer network. The learning support system has two parts: the learning support subsystem and the student model subsystem. Each subsystem is built on a personal computer running Windows 95/98, and connected computer network using TCP/IP. The learning process data received on the learning support subsystem are sent to the student model subsystem, that analyzes the state of the student's understanding. The results of the analysis are fed back to the teaching strategy module in the learning support subsystem, and used as support for the student.

Key words : environmental learning support system, computer network, student model, personal computer, Windows

Title: Torque Transmission Characteristics of a Hooke's Joint
Author: Masayoshi KATO, Daisuke TATSUO

題目：フック継手のトルク伝達特性に関する研究
著者：加藤正義・辰尾大介

Abstract

The purpose of this study is to explain the torque transmission characteristics of a Hooke's joint, and to present the analytical and experimental methods concerning its torque transmission. When the Hooke's joint transmits a moment of force, the law of action-reaction holds between the cross pin and yokes, elements of the joint. This basic law of mechanics means that the Hooke's joint can transmit a moment of force only in the direction perpendicular to the plane that contains the cross pin. Two vectors were introduced to analyze the movement of the cross pin and the yokes. Each direction of the vectors corresponds to that of the two pins forming the cross pin. As a result, vector analysis produced a mathematical expression for the transmission moment of the Hooke's joint. Each torque for the driving shaft and the driven one to rotate is represented by a component to each shaft direction of the transmission moment. This produces a torque transmission rate of the Hooke's joint. The torque transmission rate changes twice while the driving shaft makes one revolution, the minimum value becomes near zero and the maximum value infinity as the joint angle approaches 90 degrees.

Key Words: Hooke's joint, Cross pin, Law of action-reaction, Transmission moment, Torque

Title: Evaluations of the Letter Recognition with Neural Networks
Author: Masaaki NISHI, Shinnosuke ODA, Junji FURUYA

題目：ニューラルネットワークによる文字認識の評価
著者：西　正明・織田真之介・降矢順治

Abstract

Neural networks have generalization and discrimination abilities, and their application in various fields has been much studied. In this paper, we apply neural networks to letter recognition. We examine adding delay elements to the neural networks, cluster division, and feature extraction for the letter data, and we show that they are effective for shortening the learning processing time and improving the letter recognition rate. We also apply neural networks with multiple steps of delay elements to the OCR letter recognition using a scanner, and we show that they can recognize handwritten letters on paper better than before.

Key words : letter recognition, neural network, delay element, cluster division, feature extraction.