Rotating bending fatigue tests were carried out for maraging steels using specimens heat-treated at different under-aging conditions to prepare specimens with 4 kinds of hardness and the dependence of hardness on fatigue strength was investigated not only for a surface fracture but also for an internal fracture using electro-polished and shot-peened specimens. All surface fracture generated surface fracture under the high stress, when it was shot-peened specimens in case of electro-polished specimens, and internal fracture was generated under the low stress. S-N curve of shot-peened specimens showed two step shape. Hardness dependence of the fatigue strength is evaluated in surface fracture and internal fracture. They not recognize even in Hv670 on the limit in case of the internal fracture, while about Hv600 becomes a limit in case of the surface fracture.

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Rotating bending fatigue tests were carried out for a shot-peened managing steel in order to investigate the effects of shot peening on the fatigue strength and the fracture mechanism. Fatigue strength was markedly improved by shot peening because of hardening and generation of compressive residual stress in the surface layer. Origin of fatigue fracture changed from the specimen surface at high stress levels to an inclusion in the interior of specimen at low stress levels. And at the middle stress levels, both fracture modes were observed. Consequently, the shape of S-N curve of shot-peened specimen was complex corresponding to the change of fracture mode. Fatigue strength at low stress levels, where internal fracture occurred, increased by formation of reversion austenite. This is mainly caused by the suppression effects of reversion austenite to the growth of a small crack and the intergranular crack. By formation of reversion austenite, a clear fish-eye was observed.

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A6061-T6 aluminum alloy sheet with three millimeter thick was friction thermomecanical processed under processing conditions at various rotating speeds and feeding speeds from 800 to 2000rpm and 50 to 400mm/min, respectively. Microstructure on cross section of the friction thermomechanical processed sheet was investigated by mean of an optical microscopy and scanning electron microscopy method in order to characterize the metallurgical plastic flow pattern in the stir zone and evolution in size and morphology of the matrix grain structure from original parent sheet. Microstructure with good quality was obtained at the optimum FTMP conditions of the 1200〜1500rpm of tool rotating speeds and 100〜200mm/min of tool feeding speeds using a tool with 10mm of shoulder diameter, and 3mm of pin diameter. Stir zone in a central part consisted very fine recrystallized grain structure with 3.5μm in mean grain size. However, the recrystallization in stir zone can lead to drastic degrease of its impact toughness comparing with the base material. Many oxide inclusions are distributed at microstructure. Fracture mechanical analysis reveals that the toughness degradation is attributed to premature damage evolution such as microcrack initiations into the coarse oxide inclusions.

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In recent years there has been a rising interest and researches in using high strength natural fibers as filler for biodegradable resin matrix composites. The present work deals with mechanical elements of deformation and fracture behavior of bamboo fiber bundle(Phyllostachys pubescens). The steam explosion treatment was applied to extract the bamboo fibers from natural bamboo. Dynamic tensile test, using a Hopkinson bar of low impedance bar(polyvinyl chloride, PVC) setup and conventional quasi-static test were carried out with this fiber. The tensile stress-strain response of bamboo fiber was observed elastic material response. A maximum strength bamboo fiber was given from near the outside of bamboo culm. Fiber strength decreased with increasing gage length in test piece. Experimental results show the fracture strength of the bamboo fiber has strong dependence on its volume. The PVC long bar was ascertained to be quite useful for a device measuring stress waves in dynamic tensile tests, if the behavior of the wave propagation in the PVC bar such as the decreasing rate of the wave amplitude and the propagation velocity are obtained by wave propagation pre-experiment beforehand.

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The vector control of induction motor is widely used. This method needs accurate motor parameter but the stator and rotor resistance vary due to motor temperature variation. The indirect field oriented control of an induction motor requires value of rotor resistance only, but the direct field oriented control method with rotor flux observer requires value of not only rotor resistance but also stator resistance in the controller. The vector control of induction motor without a speed sensor requires the estimations of rotor flux and the rotor speed. Since the estimations use the machine parameters and the stator voltage and current components as input quantities, the stability of the system is sensitive to the variations of the machine parameters. In this paper, the direct field oriented control system of the induction motor without a speed sensor using the adaptive rotor flux observer (MRAS method) is studied. The step responses are calculated to investigate the influences of controller parameters.

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Structural and electrical properties of AgInS_2 (AIS) thin films grown by single-source thermal evaporation method were studied. The films were annealed from 100 to 500℃ in air after the evaporation. The X-ray diffraction patterns indicated that the polycrystalline AIS films were successfully obtained by annealing above 300℃. The samples annealed above 300℃ have band gap energy of 1.90eV. A grain size increased with increasing annealing temperature. The maximum grain size of the samples was 2.7μm. And all samples were n-type conduction by thermo-probe analysis. The photoluminescence spectra of the samples obtained the broad spectra with the peak at 1.8eV. The dominant defect of the samples obtained by annealing above 300℃ was sulfur vacancy. The carrier concentration of samples obtained by annealing above 400℃ was about 1X10^<19>cm^<-3>. The carrier mobility of samples obtained by annealing above 300℃ increased the increasing with annealing temperature.

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Sensor elements of (Sm, Ca)CoO_3/MOx(M=transitiom metal, Zn, Sn, Fe) were made by mechanically two sintered pellets. (Sm, Ca)CoO_3 were prepared by valence control. In these sensor elements, (Sm, Ca)/WO_3 elements showed low sensitivities to ethanol, hydrogengas, benzene, but (Sm, Ca10, 20%)CoO_3/ZnO elements showed high sensitivities at 100, 200℃ to ethanol. And (Sm, Cal0%)CoO_3/ZnO showed high sensitivity to benzene at l00℃.

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これから数回にわたって書き続けられる予定の小論は、筆者の「並木栗水研究」の一環をなすものである。そして、「並木栗水研究」は小論の標題が示しているように、更に筆者の「幕末維新における新朱王学の展開」というテーマの一翼を担うものである。並木栗水は、幕末の朱子学者にして著名な擾夷思想家大橋訥庵の衣鉢を継ぐ者である。しかし、その師訥庵の生が優れて政治的であったのとは異なって、栗水は終世僻邑にあってモノローグの形で自己の思想を形成した。由来、栗水を知る者は極めて稀れである。その意味では、栗水はノーマンの表現を借りていえば「忘れられた思想家」である。本稿では栗水とその講友楠本碩水・東沢潟の生が、世代的には明治の啓蒙思想を担った最初のインテリゲンティア集団明六社同人のそれと全く重なるという事実を指摘して、その比較を試みようとした。ただ、前者が後者と決定的に異なる点は、後者が明治という時代に自己の抱懐する課題を具現化する積極的な展望を見出し得たのに対して、前者はその時代を例外者としての自覚に生きたところにあった。そして、例外者としての自覚に生きた彼等の苦悩に満ちた、しかし真実なるその生涯を後代から振り返ったとき、栗水には栗水の、同様に碩水には碩水の、沢潟には沢潟の、独自なる体験的背景が存するのだった。そのような独自なる体験的背景を明らかにすることによって、彼等の生を歴史的に定位しようというのが小論の課題である。行論上、本稿では碩水の生の検討から始めた。

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This paper aims to present the current situation of education of the engineering ethics in the National College of Technology in Japan (hereafter abbreviated as NCT). It is well known that the course of engineering ethics in NCT has been comparatively recently introduced and become major one quite quickly. In the first part of this paper the history and reason for the introducing the engineering ethics are analyzed. The second part explores the current tendencies of engineering ethics in NCT. The number of NCT which offers the course in engineering ethics and other factors are shown based on the survey conducted across the country. The last part discusses the possible future of education of engineering ethics in NCT. Improvement of the course with reference to other fields of applied ethics, for example, is suggested in this part.

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The aim of this paper is to explore educational systems in Vietnam under the current constitution and the educational law which came into effect in 1998 by analyzing legal systems in the country. First, we survey the outline of educational systems in contemporary Vietnam. The next two chapters discuss the legal system and the higher educational system of Vietnam focusing on the moral and ethical education. The last chapter provides suggestion which is conceived from education for the engineering ethics in Vietnam. This paper, as a whole, will contribute to the study of educational system in Asia.

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本『研究報告』第三十八号掲載分に引き続き、幕末維新期の儒学者である楠本端山の漢詩に訳注する。本稿分も端山および宋明儒学者一般の漢詩の特徴がよくわかる作品である。中国の文学や思想を背景としてそれらが解釈されなければならないことも、これまで紹介した作品と同様である。本稿では二つの作品に訳注した。どちらも政務から離れた生活を題材としたものである。このような場合、宋明儒学者の詩は内容が類型化しやすい。すなわち花鳥風月と自分とのかかわりをうたう。静かに落ち着いて暮らしている自画像を描く。当然、言語表現もそれらに見合ったものとなり、一見のどかな光景がそこに現出されている。ただし、そののどかさは単に一時的な心境ではない。儒学者としての志や在るべき人生そのものの表出という意味を持っている。すなわち、元来は政治家でありながら政治世界に浮沈するのをよしとしない矛盾とも言える生き方が提示されているのである。儒学者はさまざまな人物や思想、言語と交渉してきた。彼らの詩にみられる言語空間は、長い歴史の問に練りあげられてきたのである。詳しくは【注】に挙げた資料を見ていただきたい。

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Because of the popularization of higher education, various students have begun to enter universities and colleges of technology. Our school (MNCT) is no exception. The quality of incoming students has changed dramatically in the past few years. As students of the college of technology, the new generation of the students often lack basic academic skills, social manners, self-respect, mental stability, and personal relations or consciousness. The number of the students with these problems seems to be increasing every year. The purpose of this study is to seek an ideal way to support students with various problems. First, we analyzed the questionnaire survey conducted for MNCT students by the Office of Student Counseling for the past four years. The survey consists of the following topics : common worries of all students, the different ways students cope with personal anxieties, the level of satisfaction with school life, causes of personal anxieties, and student's mental health. Second, we compared the result of the survey with the related parts of the class evaluation questionnaire survey conducted by the Department of School Affairs Guidance every year. In the end we found common issues relating to students' mental growth, personal relations, and emotional problems between the aforementioned two surveys. As a result, we need to argue the importance of introducing a new system to support students' human growth as young adults; that is, we need to create lectures for mental health and social manners for students.

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近年工学教育でも注目を浴びている問題設定解決型学習(PBL)は従来の授業形態(LBL)と対比して用いられることが多い創造力育成の一つの手法である。PBLを取り入れた教育ではLBLと比べて学生が楽しんで授業に参加するなどの教育効果が期待できる。本報告では著者が担当している機械工学科の実験においてPBLを実施することを念頭に置いて、PBLを実施するのに適当なテーマの選定及びそのテキスト概要などについて検討した。そして、3年生、4年生の実験の中では3年生の基礎実験が適切であると考えられ、切削抵抗の測定の実験テーマのテキストを検討した。その結果、実験条件の範囲を広げて実験し、エクセルでそのデータをグラフ化し、近似式を求めるなどを工夫することでPBLを実施できることが分かった。この内容でテキストを作成し、今後は実際に実験で検証する予定である。

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本稿は実用的文章を作成させる授業について述べたものである。授業目標は、各種試験あるいは仕事現場で有効な文章表現のあり方を学生に認識してもらい、また、そうした表現にできるだけ習熟してもらうことである。したがって読書感想文や随筆的な文章等へは直接には関与しない。授業科目は国語、該当学年は第3学年と専攻科第1学年である。本稿の主な内容は以下のとおりである。(1)実用的文章を作成させる必要性を明らかにする。(2)授業の内容としては、(1)意見文を作成する授業、(2)説明文・描写文を作成する授業、(3)段落の作り方に関する授業、(4)悪文を直す授業、(5)その他、がある。それぞれの授業について現状を報告し問題点をいくつか挙げ、担当者である私の対応や考えを付記する。本稿では(1)について重点的に述べる。(3)授業に関連した若干の考察に言及する。

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The purpose of this paper is to introduce an approach for improving upper grade students' English proficiency at Miyakonojo National College of Technology, where the English curriculum for the fifth-year students was revised in 2004. Since then, the fifth year students have been obliged to take English for two credits, which had been an elective subject for several years. This paper also refers to some methods the English teaching staff have taken in order to make the fourth-year and the fifth-year students acquire reading skills which enable them to read intensively or rapidly, and furthermore, to improve their TOEIC scores.

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