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過重力下で栽培したヒメツリガネゴケの光合成能力と形態変化
Get PDF京都工芸繊維大学博士（学術）10×gおよび3×gの過重力下で栽培したヒメツリガネゴケの、光合成速度測定、CO₂コンダクタンス測定および形態変化の観察を行った
Development of Polyoxymethylene Composites
Get PDF京都工芸繊維大学博士（学術）Good balance of mechanical, thermal, chemical and wear properties is a strength point of the engineering thermoplastic as Polyoxymethylene (POM). However, the application of POM has a limitation as a low toughness. Thus, this is the one drawback that several researchers try to overcome. In this research the material and processing were designed to introduce the new function and possibility of production for POM. The adaptation of blending technique with a biodegradable thermoplastic as Poly (lactic acid) or PLA was the first candidate. The super ductility was generated from this blend system. The elongation of POM/PLA was over 300% under tensile testing speed of 10 mm/min. It was noted that the PLA content should be limited in the range of 30 – 40 wt.% to remain the ductile property. Furthermore, the limit of POM/PLA fabrication was found. With high PLA content, the in-completed distribution of POM rich phase was found and resulted on poor mechanical properties. However, the poor distribution could be improved by increasing of injection speed. That also improved mechanical properties too. Short glass fiber reinforced POM composite by direct fiber feeding injection molding (DFFIM) process was the second candidate for improving mechanical properties of POM and POM/PLA blend. The various matrix feeding speed, screw rotational speed and also number of fibers roving related to the fiber loading content and fiber. The decreased matrix feeding speed and increased screw rotational speed led to the increasing of fiber loading content. For product quality, the tensile properties of POM and POM/PLA blend were successfully improved by reinforcing short glass fiber. The tensile modulus and tensile strength of all materials increased with the increasing of fiber loading content. However, at high fiber loading content, the agglomeration and misalignment of fiber appeared on the fracture surface of POM and POM blend composites and resulted the non-increasing of tensile strength. The strength prediction was used to estimate the maximum strength of those materials. The strength of POM can be improved at least 18 %, if the fiber distribution and fiber orientation are modified. The single edge notch was marked on the sample to simulate the failure of material under the crack and compared to un-notched sample. The fracture toughness of each material depended on the load that was applied to open crack. The materials that presented the brittle crack initiation resulted the higher fracture toughness when compared to the initiation of crack as ductile or crazing behavior. While the sensitive on notch depended on the fracture transformation between un-notched and notch samples. In the case of POM, the plastic deformation still occurred in the initial crack even finally fractured as brittle. At the same time, POM/PLA blend presented the low fracture toughness, but less sensitivity on the notch. The percent crystallinity at crack root affected the fracture behavior of the super ductility of the POM/PLA blend. The low crystallinity at 1000 um of crack depth led to the super ductile fracture whereas the crack depth at 500 um with high crystallinity presented only the small crazing and propagated to brittle fracture. The fracture behavior under the open hole notch was also simulated. The stress whitening relates the low sensitivity on the open hole notch of materials. Moreover, if the materials have ductility, the crack propagates slowly. On the contrary, if materials deform without the sign of stress whitening, their failure is quite serving and rapid. In the case of POM composite, the increasing of glass fiber loading content had an influence on the increasing sensitivity of open hole notch. Crazing of matrix, stress whitening and fiber pull out were found on GF/POM fracture surface, whereas the low sensitivity on notch as neat POM presented large stress whitening zone and fanlike crack pattern. Finally the effect PLA on wear performance of the POM/PLA blend was investigated by the sample sliding against carbon steel condition. The various pressured loads were applied to sample surface to examine the friction coefficient value of each sample. The increasing of an applied load led to the decreasing of coefficient of friction and increasing of wear weight loss, whereas the increasing of PLA content led to the increasing of coefficient of friction. The high sensitive on heat generation of PLA caused the occurring the thermal softening and melting behavior and the high coefficient of friction and this phenomenal also affected on POM/PLA blends
里見宗次 二つの「ＪＡＰＡＮ」
Get PDF京都工芸繊維大学広報誌KIT・NEWS, Vol.44, 2017.03, 美術工芸資料館収蔵品紹介36, pp.15-16著作権保護期間中のため、文中のポスター３枚は掲載を見合わせております。悪しからずご了承ください
「伝統工芸の言葉と技の伝承が秘められた職人の暗黙知の解明」研究成果報告書
Get PDF平成29年度（2017年度）科学研究費補助金助成 挑戦的研究（萌芽） 課題番号 17K18483成果報告書「伝統工芸の言葉と技の伝承が秘められた職人の暗黙知の解明」における研究成果と本研究課題の結論となる論文を日本語と英語で掲載した。平成29年度（2017年度）科学研究費補助金助成 挑戦的研究（萌芽）研究成果報告書 課題番号：17K18483 研究代表者：澤田, 美恵
日本の地方公共団体を主体とするシンボルマークによる地域性の表出とその造形―市町村の自治体紋章を中心として
Get PDF京都工芸繊維大学博士（学術）本研究の目的は，自治体紋章の黎明期より時代を追って，デザイン的見地から図案の造形方法と図案モチーフの関連性を考察することにある。また，自治体紋章による地域固有性の表出方法を探求することにより，地域を主題とするデザインを歴史的に再考する意図を含んだ。図案の変遷とともに，自治体紋章が内包した時代性を明らかにし，日本のグラフィックデザインの系譜において，自治体紋章図案をどのような視座で捉えるべきかを問うものである
土壁構法の研究「版築」「団子積み」「練り土積み」の検証実験をとおして
Get PDF京都工芸繊維大学博士（学術）本研究は、昔から日本にあった土壁構法である「版築」「団子積み」「練り土積み」について、現存する事例を調べ、検証実験をとおして、施工方法を記録し、その活用可能性について検討するための基礎研究である。 本論文で取り上げる「団子積み」「練り土積み」の2つの用語は、一部の左官職人の口語を基に筆者が定義するものである。どちらも湿った土を積み上げて成形しながらつくる構法であるが、その工程のなかで「団子積み」は一旦土を団子状にしてから少し時間を置いてつみあげていくものである。「練り土積み」は、団子にはせず、そのまま土を積み上げて成形しながらつくるものを指す。 地球温暖化が進む現在、ライフサイクルを通じてエネルギー消費の低い建築が求められている。シックハウス対策や、自然志向の快適欲求、身近にあるものを使って生活の満足度を得るといったライフスタイルの実現に於いて、その土地にある自然の土を使ってつくる土壁は、有効な素材として注目されている。中でも上記３つの構法は、１）蓄熱体としての利用に、厚みのある土壁が有利であること。２）高い技術を必要とせず、施工者の裾野の広い構法であること。３）構法に型枠の有無の違いがあること４）現存するこれらの構法を用いた建築物や工作物は、耐久性が高いこと。以上の理由より、現代における土壁利用を広げるに当たりふさわしい構法であると考えた。 第1章は、研究の背景と目的、研究の方法と本論文の構成を述べている。さらに、本論文で取り上げる「版築」「練り土積み」「団子積み」の他にも様々な土壁構法があることを確認し、本論文で取り上げる構法を中心に、筆者が実際に訪ねた土壁事例と特徴を纏めた。 第2章は、版築の施工性、設計上の留意点を知るため、2001年5月から、2002年3月にかけて４畳半程度の版築構造の実験棟「版築造実験居室」(2002)を計画、検証実験としての建設をおこなった。版築のテストピースの１軸圧縮試験、建設にかかる日数、人数、施工費、さらにはセルフビルドで版築をつくることのメリットとデメリットについて検討した。さらに、2004～2013年にかけて、本研究で得られた一連の知見を基に、版築を用いた建築作品「H邸」(2004)、「清水ヶ丘の家」(2005)、「セトレマリーナびわ湖」(2013)、ほか17の事例が実施され、版築の一般化と普及に繋がった事について述べた。 第3章では、「団子積み」と「練り土積み」に焦点を当て、２つの構法のいずれか、もしくは両方を用いた3つの建築や工作物によるプロジェクトの検証実験について、計画と概要、材料、道具、施工の要領をまとめ、工程、施工日数、人数等を比較、考察した。 3つのプロジェクトと使用構法は下記のとおりである。 1.「公園灰屋」における「団子積み」 2.「藁葺き泥小屋」における「練り土積み」 3.「かまど」における「団子積み」と「練り土積み」の混合 検証実験の結果 「団子積み」と「練り土積み」の施工特性をまとめると、①労働力（h/㎥）が「団子積み」より「練り土積み」の方が少なかった。②土に混ぜる水の量は、「団子積み」の方が「練り土積み」より多かった。③土を練る際の藁は、「団子積み」では加え、「練り土積み」は加えなかった。④「団子積み」「練り土積み」共、建物平面に曲面が多用されている場合は、型枠コストと、造形のしやすさの面で、型枠を必要とする版築よりも優位である。⑤1日の壁の施工可能高さは「団子積み」「練り土積み」共600㎜程度である。 さらに、「版築」「団子積み」と「練り土積み」および、それらの構法に類似する湿った土を積み上げる土壁構法に対する関係性を図示した。 第4章は、土壁を活かしたパッシブデザインとして、土壁構法の中でも、締め固められた厚みのある版築に焦点を当てた。基礎編として、2章で取り上げた版築造実験居室を用いて、版築の熱容量が生かせる仕様を探るため、改修仕様の組み合わせを、性能予測を行いながら設計を行ない、実際に改修をおこなった。改修前の夏と冬の熱性能実測、夏と冬の２段階の改修計画、改修・実測をおこなった。これらを通して版築の熱容量が効果的に作用していることが確認された。 さらに、この研究の応用として、版築を多用したホテルの設計段階に於いて、客室界壁に用いられる版築の蓄熱効果を確認するため、客室の構成素材や、使い方による冷房負荷比較を、シミュレーションを用いて行なった。その結果、外気温が18～26°Cの際、冷房に頼らず外気導入をおこなうことにより、75%の年間冷房負荷を削減できることがわかった。そして、効率のよい外気導入の実現のため、開口部の位置も通風のシミュレーションを用いて検討した。 建設後の評価として、開業後の７月に実測し、計画時の予測と比較・分析した。さらに、宿泊客が冷房の使用や外気導入を積極的に行っているかどうか、宿泊者162組にアンケート調査し、考察した。リゾートホテルの場合、長期滞在には人工的な冷房よりも、風の冷却効果や蓄冷による自然な涼しさが好まれる場合も多く、省エネ効果に加えて自然志向の快適欲求に応えることができると考えられた。 第5章は総括として、各章のまとめと「版築」「団子積み」「練り土積み」の構法比較を行った。 3つの構法の活用可能性を広げるための今後の課題として、 1)壁厚壁高さの指標を見出すこと 2）土の選定・配合の指針を立てること 3）施工者による違いと利点を示すこと 4)版築壁をはじめとする、厚みのある土壁の熱容量を生かしたパッシブデザインのプロトタイプを提示すること 以上の4点が挙げられた
Manipulation of Silicon Nitride Biomaterial Surfaces for Enhanced Osteoconductivity and Bacteriostasis
Get PDF京都工芸繊維大学博士（工学）Silicon nitride (Si3N4) has a distinctive combination of material properties desirable for orthopaedic implants, such as high strength and fracture toughness, phase stability, biocompatibility, hydrophilicity, radiotranslucency and resistance to biofilm formation. Its unique oxynitride surface, populated by native amino- and hydroxyl-terminated functional groups, lends itself to easy tuning via simple thermal, chemical, and mechanical treatments. In this thesis, Si3N4 surfaces subjected to various treatments, such as grinding and polishing, chemical etching, and annealing in nitrogen or air, were characterized using a variety of microscopic and spectroscopic techniques, streaming potential measurements, and static contact angle measurements. Significant differences in surface properties were observed with isoelectric points ranging from 2 to 5.6, and moderate to extremely hydrophilic water contact angles varying from ~65° to ~8°. With promising surface properties observed, in vitro tests using cells from the SaOS-2 line were employed for an assessment of the modified surfaces’ osteoconductive potential. While all Si3N4-derived surfaces were found to encourage osteoid production and mineralization, samples annealed in N2 exhibited by far the greatest volume of deposited hydroxyapatite. Further observation revealed that the cells preferentially clustered on islands of SiYAlON phase at the surface of these samples. Motivated by this result, a synthetic glaze designed to mimic the composition of the SiYAlON islands was applied to Si3N4 substrates and subjected to a similar battery of tests. As hypothesized, the glazed surfaces induced even more osteoid formation and mineralization than their N2-annealed precursors. In vitro testing was also employed to observe potential inhibition to biofilm formation by Staphylococcus epidermidis and Escherichia coli, both commonly responsible for post-surgical infection, due to changes in surface chemistry. It was found that treated surfaces retained all or most of as-fabricated Si3N4’s inherent resistance to biofilm formation. Further understanding was gleaned when Raman spectroscopy was employed to probe interactions between the samples and living cells, both SaOS-2 and the bacterium Porphyromonas gingivalis. Shifts in bands associated with metabolic indicators illuminated some of the mechanisms at play during these interactions. This work demonstrates that modification of Si3N4’s surface can enhance its native osteoconductivty without compromising its bacteriostatic character. Novel SiYAlON formulations show promise not just as a surface enhancement for silicon nitride, but also as a novel bioactive material that can be infused into or coated onto existing products to enable desirable biologic interactions
Scientific research on Japanese traditional culture - Cases of “Kana-ami”, the way of tea and calligraphy
Get PDF京都工芸繊維大学博士（学術）Japan is an ancient country with more than one thousand years of history and a lot of traditional handicraft techniques. Especially in Kyoto, Kyoto has set the quality standard for Japanese arts and crafts. The city remains the most important center of traditional Japanese crafts nowadays. In the ancient period, numbers of old craftsmen improve their skill in order to head to Kyoto for serving the Emperor. Nowadays, the traditional industry has been developed well in Japan. The traditional handicraft，traditional ceremony and traditional artwork have deeply entrenched within Japanese people’s heart. With the advent of the industrial revolution and mechanization production, Mechanical products have been an extensive application in modern Japanese daily life, which replaces the most of the Japanese traditional product. Particularly worried about is that young person willing to engage in fewer and fewer people of traditional crafts. One of the important restrictive problems in future of Japanese traditional industry development is that learners have to accept training with a long time in order to become an excellent traditional craftsman. In general, nearly all of handwork skills and knowledge were passed to learners by oral teaching and action imitation. Therefore, it is very difficult for most of the learners to master and duplicate those excellent skills. They have to take considerable time and effort to do practice again and again with the aid of indescribable motion perceiving. Therefore, it is not easy for a learner to catch the key technical point of handwork skill only based on teachers’ demonstration. In other words, scientific understanding for expert’s handwork skill is useful in the real teaching application. It is urgent time to pay attention to reduce the time of training cycle and keep healthy development of this traditional industry. In this research, scientific technology was applied to the talent cultivation of traditional industry. The emphasis of this research was on the study of the different human factors between expert and non-expert influenced on traditional skills. For a better explanation that the scientific technology how to catch the key points of traditional skills from the most outstanding masters, “Kana-ami”, The way of tea and calligraphy, three application cases were paid attention, which represent the traditional handicraft, traditional ceremony, traditional artwork, respectively. In the first case of “Kana-ami”, the structure, aesthetics and performance characteristics of “Kana-ami” hexagons were clarified by comparing products made by expert and non-expert. The expert and non-expert’s consecutive fingers behavior of weaving motion were investigated by motion analysis system, especially the continuous working conditions and its relationship with final products’ structure issue also focused. In addition, the related hexagonal structures were also investigated for comparing. It is found that expert’s working motion could support his continuous weaving process and stability structure compared to the non-expert. In the second case of the way of tea, the surface bubble distribution of the tea made by expert and non-expert were focused. The three tea whisks and five tea bowls were selected and clarified as factors influencing on tea making. It found that the tea whisks and tea bowls had a very small impact for the expert on the bubble distribution of the final tea. Furthermore, the expert and non-expert’s tea making motion was investigated by the high-speed camera system. The subjects’ behavioral motion characteristics of tea making motion were inspected and discussed. The difference of tea making motion between expert and non-expert was found clearly. In the third case of calligraphy, in order to provide some artistic guidelines and evaluation suggestions, a numerical evaluation system of calligraphy was proposed and established. The characteristics of four type fonts and calligraphy works were clarified clearly by this system in order to verify this system’s practicability. Four type fonts of “Kaisho”, “Gyosho”, “Sousho” and “Hiragana” were investigated by evaluation system. The “Hiragana” works and “Kanji” works were also measured in order to compare the style of “hiragana” and “Kanji”. Furthermore, the writing characteristics were also paid attention by writing digitizing index. The motions of two experts and two beginners were also recorded by video cameras, and analyzed by software. All subjects' writing characteristics were found. Based on three cases of scientific research on Japanese traditional culture, tacit knowledge of expert’s technique was clarified clearly by numerical method. In the future, it may contribute to learners to program a reference for helping the learner training
New material design of multi-stereo block poly(lactic acid)s by controlling the block length and the total molecular weight
Get PDF京都工芸繊維大学博士（工学）In this study, multi-stereo block poly(lactic acid)s (multi-sb-PLAs) with molecular weights of approximately 60,000 and 130,000 with various block lengths were synthesized from di-block copolymers consisting of L- and D-blocks with the same length are connected with 1,12-dodecanediol (DMG), an initiator and hexamethylene diisocyanate (HMDI), a chain extender alternately. The effects of the block length and the molecular weight on the thermal properties, the isothermal crystallization behavior and the higher order structure of the multi-sb-PLAs were investigated.Poly(lactide) (PLA) is one of the bio-based polymers synthesized from renewable resources and has been expected to be replaced to the conventional fossil resource-based materials. Blending of two isomeric PLAs, poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA), leads to the stereocomplex (sc) formation. However, both hc and sc tend to co-exist in the simple blend of PLLA and PDLA. On the other hand, only sc tends to form in the block copolymer of L- and D-lactic acids (sb-PLA). In this study, oligo-D-lactic acids with various molecular weights were synthesized by the 1st ROP of D-lactide. Then tri-sb-PLAs were synthesized by the 2nd ROP of L-lactide using oligo-D-lactic acids as a macro-initiator. Further the chain extension reaction was performed for these tri-sb-PLAs to obtain multi-sb-PLAs. This method is characterized by the well controlled block length and composition of the resultant multi-sb-PLAs because they ought to be determined by the molecular weights of the starting PDLA and PLLA prepolymers. Although the total molecular weight of di- and tri-sb-PLAs are directly related to the block length, that of the multi-sb-PLA can be designed independently of the block length. So the effects of the block lengths and the total molecular weight of the multi-sb-PLA on the thermal property and the crystallization behavior can be examined separately
Dynamics of Crack-Growth in Filled Elastomers
Get PDF京都工芸繊維大学博士（工学）The characterization and understanding of the crack-growth in elastomers have been an important issue both in polymer physics and industrial rubber products. In this thesis, two characteristic phenomena are investigated experimentally and analyzed while focusing on the effects of nonlinearity in elasticity and/or viscoelasticity: (1) the crack-growth rate v transition between two distinct regions of the slow mode and fast mode with the small change in the input tearing energy Γ, and (2) a power-law relationship between v and Γ in the fast mode region. The types of rubber and filler, concentrations of filler Φf and cross-link cx, and temperature T are extensively varied in order to change the degree of nonlinearity in elasticity of the elastomers. The shapes of crack-tip are characterized by two specific parameters, i.e., the deviation δ from the parabolic shape expected by linear elastic fracture mechanics (LEFM) and the parabolic curvature a. The Γ dependences of δ and a are successfully explained by weakly nonlinear elasticity theory of dynamic fracture (WNLT), which considers the second-order nonlinear effect in elasticity to LEFM, unless δ exceeds a limit value δc, independently of the types of rubber and filler, Φf, cx, and T. The value of δc depends on types of rubber and filler, whereas it is independent of Φf, cx, and T. The magnitude of the threshold tearing energy Γc for the onset of the crack-growth rate transition shows a good correlation with the fracture toughness Wc reduced by μ(1)3/μ(2)2 (μ(1): linear shear modulus, μ(2): second-order shear modulus), which is a measure of the nonlinearity in elasticity in WNLT. This result indicates that Γc is governed by the combined effect of the degree of nonlinearity in elasticity and the fracture toughness. A power-law relationship between v and Γ, i.e., Γ ~ vα, is also investigated. We find a universal relation between α and the exponent κ of the stress relaxation function G(t) ~ t-κ in the glass-rubber transition regime in linear viscoelasticity. The relation between α and κ is successfully explained by the existing theories which consider the contribution of linear viscoelasticity to LEFM for elastomers with low Φf and high cx, whereas that for elastomers with higher Φf and lower cx exhibits a finite deviation from the theoretical expectation