OKUBO Kazuya
Faculty of Science and Engineering Department of Mechanical Engineering and Science
Professor
Last Updated :2024/05/02

Researcher Profile and Settings

Research Interests

  • 有限要素法FEM
  • 無段変速機CVT
  • 伝動変速機
  • 非線形構造
  • 超弾性
  • き裂じん性
  • 疲労損傷
  • 材料信頼性
  • マイクロ材料力学
  • 複合材料
  • FEM
  • Finite Element Method
  • CVT
  • Continuous Variable Transmission
  • Power Transmission
  • Nonlinear Structure
  • Hyper Elastic
  • Crack Toughness
  • Damage Mechanics
  • Fatigue
  • Material Reliability
  • Fracture
  • Strength
  • Micro Mechanics
  • Composites Materials

Research Areas

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Machine materials and mechanics

Research History

  • Strength and Fracture Mechanics of Composites Materials
  • Structural Engineering
  • Mechanics of Adhesion system
  • Mechanics of Power Transmission Systems

Research Experience

  • Graduate School of Doshisha University, Specialty of Engineering, Professor, 2012/04 -
  • Graduate School of Doshisha University, Specialty of Engineering, Professor, 2010/04 - 2012/03
  • Graduate School of Doshisha University, Specialty o Life and Medical Science, Professor, 2008/04 - 2010/03
  • Doshisha University, Development of Engineering, Professor, 2007/04 -
  • Graduate School of Doshisha University, Specialty of Engineering, Associate professor, 2003/04 - 2007/03
  • Doshisha University, Development of Engineering, Associate professor, 2001/04 - 2007/03
  • Doshisha University, Development of Engineering, Lecturer, 1999/04 - 2001/03
  • University of Delaware, Center for Composite Materials, Visiting Research Associate, 1999/09 - 1999/12
  • Doshisha University, Development of Engineering, Part‐time lecturer, 1993/04 - 1999/03
  • Nitta group companies, Development department, Employee, 1992/04 - 1999/03
  • Doshisha Junior High School, technology education, Part‐time lecturer, 1987/04 - 1992/03

Education

  • Doshisha University, 工学研究科, 機械工学専攻, - 1992
  • Doshisha University, Graduate School, Division of Engineering, - 1992
  • Doshisha University, 工学研究科, 機械工学専攻, - 1989
  • Doshisha University, Graduate School, Division of Engineering, - 1989
  • Doshisha University, 工学部, 機械工学第2学科, - 1987
  • Doshisha University, Faculty of Engineering, - 1987

Degree

  • Master of Engineering, Doshisha University

Association Memberships

  • 自動車技術会
  • 日本複合材料学会
  • 日本機械学会
  • 日本材料学会
  • 日本接着学会
  • 日本ゴム協会
  • ベルト伝動技術懇話会

Committee Memberships

  • Organizer of Kansai branchi, 2018/04 - Today, The Adhesion Society of Japan, Society
  • Board of trustees, 2018/04 - Today, The Adhesion Society of Japan, Society
  • president, 2017/04 - Today, The Society of Belt Transmission Engineers, Society
  • Editorial committe, 2016/04 - Today, The Adhesion Society of Japan, Society
  • Counsel in University for Kansai branchi, 2010/04 - Today, The Japan Society of Mechanical Engineers, Society
  • Organizer of JSMS Committee on Composite Materials, 2009/04 - Today, The Society of Materials Science, Japan, Society
  • Organizer of Kansai branchi, 2019/04 - 2021/03, The Japan Society of Mechanical Engineers, Society
  • vice president, 2015/04 - 2017/03, The Society of Belt Transmission Engineers, Society
  • Representative, 2015/04 - 2016/03, The Society of Materials Science, Japan, Society
  • Board of director, 2014/04 - 2016/03, Japan Society for Composite Materials, Society
  • Planning committee, 2009/04 - 2015/03, The Society of Materials Science, Japan, Society
  • organizer, 2001/04 - 2015/03, The Society of Belt Transmission Engineers, Society
  • Organizer of Kansai branchi, 2008/04 - 2010/03, The Japan Society of Mechanical Engineers, Society
  • Executive Committee of Kansai branchi, 2003/04 - 2006/03, The Society of Materials Science, Japan, Society
  • 関西支部企画委員, 2002 - 2005, 自動車技術会, Society, 自動車技術会
  • 力学的性質分科会書記, 2002 - 2005, 日本ゴム協会, Society, 日本ゴム協会
  • FRPシンポジウム実行委員,複合材料部門委員会幹事,関西支部常議員, 2000 - 2005, 日本材料学会, Society, 日本材料学会
  • planning committee, 2000/04 - 2002/03, The Society of Belt Transmission Engineers, Society
  • 企画委員,企画委員,幹事, 2000 - 2001, ベルト伝動技術懇話会, Society, ベルト伝動技術懇話会

Awards

  • 関西支部長賞
    Apr. 2016, 公益社団法人 日本材料学会
  • Award for Meritorious Person of KANSAI Branch of The Japan Society of Mechanical Engineers (JSME)
    Mar. 2015, 一般社団法人日本機械学会関西支部
  • 社団法人自動車技術会フェロー(2006年度)
    2006, Japan
  • 日本材料学会 平成15年度学術奨励賞
    2003, Japan

Published Papers

  • Mechanical characteristics of reclaimed carbon fibre under superheated steam atmosphere and its feasibility for remanufacturing CFRP/CFRTP
    K. Obunai; K. Okubo
    Composites Part A: Applied Science and Manufacturing, Elsevier BV, 176 107843 - 107843, Jan. 2024, Scientific journal
  • A prediction model of flat belt slippage considering rigid-slip during power transmission
    OBUNAI Kiyotaka; OKUBO Kazuya; FUKUO Ato
    Transactions of the JSME (in Japanese), The Japan Society of Mechanical Engineers, 89(924) 23-00073 - 23-00073, 2023
  • Effect of sub-micron glass fiber addition on CAI strength of UD-CFRP
    Ryotaro Murayama; Kiyotaka Obunai; Kazuya Okubo
    International Journal of Computational Methods and Experimental Measurements, WITPRESS LTD., 10(3) 271 - 281, 14 Sep. 2022, Scientific journal
  • Orbital Change of belt for Metal V-belt Type CVT (Continuously Variable Transmission) - Change of pitch angle at strings -
    Kazuki Oshima; Seiji Mitsubayashi; Kiyotaka Obunai; Kazuya Okubo
    IOP Conference Series: Materials Science and Engineering, IOP Publishing, 1250(1) 012001 - 012001, 01 Jul. 2022, Scientific journal
  • Local change of PV value on end faces of rocker pins of chain type CVT (Continuously Variable Transmission) under transmitting condition
    Ryunosuke Kikui; Kiyotaka Obunai; Kazuya Okubo; Kouhei Toyohara; Kyohei Watanabe; Hui Jin
    SAE Technical Papers, 09 Jan. 2022, International conference proceedings
  • Influence of Deformation of Elements in Width Direction on Winding Radial Displacement in Pulley Groove of Metal V-belt Type CVT
    Mitsubayashi Seiji; Hachiman Itsuki; Obunai Kiyotaka; Okubo Kazuya
    Transactions of Society of Automotive Engineers of Japan, Society of Automotive Engineers of Japan, 53(6) 1033 - 1038, 2022
  • Influence of Bending-Twisting Coupling Deformation on Pure Bending Strength and Fracture Morphology of CFRP Angle-Ply Laminate
    Kazuki Terasaki; Kiyotaka Obunai; Kazuya Okubo
    Materials Science Forum, 1067 99 - 105, 2022, In book
  • Skew of Frictional Power Transmission Flat Belt Driven by Pulleys with In-Plane Angular Misalignment
    MITSUBAYASHI Seiji; TSUTSUMI Kota; OBUNAI Kiyotaka; OKUBO Kazuya
    JOURNAL OF JAPAN SOCIETY FOR DESIGN ENGINEERING, Japan Society for Design Engineering, advpub, 2022
  • Change of Internal Force State in Element for Metal V-belt Type CVT Due to Increase of Transmitting Torque
    Mitsubayashi Seiji; Hachiman Itsuki; Obunai Kiyotaka; Okubo Kazuya
    Transactions of Society of Automotive Engineers of Japan, Society of Automotive Engineers of Japan, 53(4) 731 - 736, 2022
  • Improving Damping Properties of Carbon Fiber Reinforced Plastic Fabricated with Modified Matrix by Adding Cellulose Nanofibers : Influence of Aspect Ratio of Cellulose Nanofiber Added to Matrix on Damping Properties
    野村知正; 小武内清貴; 大窪和也
    日本複合材料学会誌, 日本複合材料学会, 47(4) 131 - 136, Jul. 2021, Scientific journal
  • Improvement of Impact Energy Absorption of Curved Thin Chopped Tape CFRP Shell by Adding Submicron Glass Fiber into Matrix
    Taiki Ueda; Kazuya Okubo; Kiyotaka Obunai; Li Bao
    Key Engineering Materials, Trans Tech Publications, Ltd., 889 59 - 64, 16 Jun. 2021, Scientific journal
  • Frictional Loss Mechanism Due to Polygonal Winding Slip of Chain Type CVT
    Yuichi Nakai; Kiyotaka Obunai; Kazuya Okubo; Junpei Hayakawa; Kouhei Toyohara; Takeshi Muramatsu
    Journal of Physics: Conference Series, IOP Publishing, 1888(1) 012011 - 012011, 01 Apr. 2021, Scientific journal
  • Influence of axial pulley misalignment on power loss in layered steel bands and of metal V-belt type CVT
    Daiki Murai; Tooru Yagasaki; Kazuya Okubo; Kiyotaka Obunai
    2021 IEEE Asia-Pacific Conference on Computer Science and Data Engineering, CSDE 2021, 2021, International conference proceedings
  • Improvement in Impact Energy Absorption of UD-CFRP by Sub-Micron Glass Fiber into Its Matrix
    Ryotaro Murayama; Kiyotaka Obunai; Kazuya Okubo; Li Bao
    Open Journal of Composite Materials, Scientific Research Publishing, Inc., 11(04) 82 - 93, 2021, Scientific journal
  • Effect of Heating Process on Flexural Strength and Toughness of CFRTP Molded by Multi-layer Press -Investigation on Effect of Residual Stress-
    Akihito Itami; Kiyotaka Obunai; Kazuya Okubo; Hiroyuki Takei
    Materials Science and Engineering, 859 12015 , Mar. 2020
  • Effect of Submicron Glass Fiber Modification on Mechanical Properties of Short Carbon Fiber Reinforced Polymer Composite with Different Fiber Length
    Nhan Thi Thanh Nguyen; Obunai Kiyotaka; Okubo Kazuya; Fujii Toru; Shibata Ou; Tomokuni Hidehiko; Fujita Yukiko
    Journal of Composites Science, MDPI AG, 4(1) 5 - 5, 02 Jan. 2020, Scientific journal
  • Change of Transmitting Properties of Rubber V-belt for CVT according to Difference of Stiffness
    TANAKA Kenichiro; OBUNAI Kiyotaka; OKUBO Kazuya; DOI Ikuhito; KATO Hideyuki
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 06_613 , 2020
  • An Method to Improve Fatigue Life of Fiber Reinforced Composite:- Introduction of Applications with Additions of Fine Fibers into Matrix -
    OKUBO Kazuya; OBUNAI Kiyotaka
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 03_kicyo , 2020
  • Stress relaxation of CFRP plate fastened by bolt in thickness direction:-Influence fastening torque, temperature condition and types of reinforcement-
    石田 貴大; 小武内 清貴; 大窪 和也; 佐々 喜紀; 石川 健
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 P_009 , 2020
  • Improvement of impact property of curved thin shell fabricated with chopped tape CFRP:- Influence of diameter of added submicron glass fiber into matrix -
    UEDA Taiki; OKUBO Kazuya; OBUNAI Kiyotaka; Li BAO
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 P_010 , 2020
  • Influence of impact energy on improvement rate of energy absorption of chopped carbon fiber reinforced FRP during drop impact test due to addition submicron glass fiber into matrix
    OKIMURA Takuma; OKUBO Kazuya; OBUNAI Kiyotaka
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 P_012 , 2020
  • Evaluation of interfacial shear strength between fiber and resin using Sprit Hopkinson Pressure Bar method
    村山 凌太郎; 小武内 清貴; 大窪 和也
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2020 P_007 , 2020
  • Design of Fixed-wing Multicopter Made from Carbon Fiber Composite Plate:-Suppression of Aeroelastic Effect in Wing Structure by Bending-Torsion Coupling Deformation-
    TERASAKI Kazuki; Obunai Kiyotaka; Okubo Kazuya
    The Proceedings of Design & Systems Conference, The Japan Society of Mechanical Engineers, 2020 1505 - 1505, 2020
  • Improvement of Fatigue Life of Plain Woven CFRP plate by Adding Cellulose Nano Fibers and Investigation on Its Mechanism
    OBUNAI Kiyotaka; OKUBO Kazuya; HAYASHI Kenta
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 69(5) 351 - 357, 2020
  • Consideration and Practice of an Effective Promotion System for Multi-Industry-Academia Collaboration in the Automobile Industry
    Akihiro Aoyama; Kiyotaka Obunai; Kazuya Okubo
    同志社大学ハリス理化学研究報告 = The Harris science review of Doshisha University, Harris Science Research Institute of Doshisha University, 60(4) 185 - 193, Jan. 2020
  • Effects of imparting polarity to epoxy matrix of carbon fiber reinforced plastic on static, impact and fatigue properties
    Ryosuke Matsuda; Kiyotaka Obunai; Kazuya Okubo; Nao Deguchi
    APFIS 2019 Proceedings - 7th Asia-Pacific Conference on FRP in Structures, 01 Dec. 2019, International conference proceedings
  • Mechanical Characteristics of Composite Reinforced by Short and Plain Woven Carbon Fiber with Vinyl Ester Matrix Modified by Submicron Glass Fiber
    Thi Thanh Nhan Nguyen; Kiyotaka Obunai; Kazuya Okubo; Ou Shibata; Hidehiko Tomokuni; Yukiko Fujita
    同志社大学ハリス理化学研究報告 = The Harris science review of Doshisha University, Harris Science Research Institute of Doshisha University, 60(3) 127 - 132, Oct. 2019
  • Impact Improvement of Tape Carbon Fiber Composite Modified by Submicron Glass Fiber
    Nhan T.T. Nguyen; Naoto Miyakita; Obunai Kiyotaka; Okubo Kazuya
    Journal of Materials Science Research, Canadian Center of Science and Education, 8(4) 21 - 21, 30 Sep. 2019, Scientific journal
  • Improvement of Static and Fatigue Durability of CFRTP Joint Using Bite Plate and Modified PP Film
    SHIOYA Wataru; OBUNAI Kiyotaka; OKUBO Kazuya; ISHIKAWA Takeshi
    Journal of the Japan Society for Composite Materials, The Japan Society for Composite Materials, 45(6) 230 - 235, May 2019, Scientific journal
  • Effects of submicron glass fiber addition on mechanical property of short carbon fiber reinforced vinyl ester resin
    Nguyen T.T. Nhan; K. Obunai; K. Okubo; Y. Fujita
    ICCM International Conferences on Composite Materials, 2019-August, 2019, International conference proceedings
  • Improvement of Interfacial Properties between Matrix and Carbon Fiber by Imparting Polarity to Plastic Matrix of CFRP
    MATSUDA Ryosuke; WATANABE Kenichi; OBUNAI Kiyotaka; OKUBO Kazuya
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2019 309 - 309, 2019
  • Prevention of interfacial strength reduction of CFRTP fabricated with MXnylon as matrix:-Investigation of molding atmosphere condition and temperature condition-
    ITAMI Akihito; OBUNAI Kiyotaka; OKUBO Kazuya; NISHIDA Hironori; TAKEI Hiroyuki
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2019 312 - 312, 2019
  • Improvement of fatigue life of metal-CFRTP bolted joint by using heat pressing before fatigue process.
    YOSHIKAWA Rikiya; OBUNAI Kiyotaka; OKUBO Kazuya
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2019 314 - 314, 2019
  • Improvement of fatigue life of plain woven CFRP by adding carbon milled fibers (CMFs) into polymer matrix:-its orientation control by applying magnetic field-
    Murayama Ryotaro; Obunai Kiyotaka; Okubo Kazuya
    The Proceedings of the Materials and Mechanics Conference, The Japan Society of Mechanical Engineers, 2019 OS0325 , 2019
  • Mechanical Properties of Submicron Glass Fiber Reinforced Vinyl Ester Composite
    Nguyen T. T. Nhan; K. Obunai; K. Okubo; O. Shibata; H. Tomokuni; Y. Fujita
    Open Journal of Composite Materials, Scientific Research Publishing, Inc., 09(04) 365 - 377, 2019, Scientific journal
  • Consideration of Industry-University Collaborative Research Framework in Drivetrain System
    Aoyama Akihiro; Obunai Kiyotaka; Okubo Kazuya
    Transactions of Society of Automotive Engineers of Japan, Society of Automotive Engineers of Japan, 50(5) 1307 - 1312, 2019
  • Industry-Academia Collaborative Research on Air Bubble Control in Oil in Vehicle power transmission system and Consideration
    Aoyama Akihiro; Obunai Kiyotaka; Okubo Kazuya
    Transactions of Society of Automotive Engineers of Japan, Society of Automotive Engineers of Japan, 50(6) 1543 - 1548, 2019
  • CHANGE OF FORCE BETWEEN SHAFTS AND WINDING PITCH RADIUS OF CHAIN TYPE CONTINUOUSLY VARIABLE TRANNSWIISSION AT STEADY STATE
    Shun Hattori, Kazuya Okubo, Toru Fujii, Kyohei Watanabe(JATCO), Jumpei Hayakawa, Atsushi lkeda
    International Journal of Robotics and Automation Enjineering, 117 , Nov. 2018, Scientific journal
  • Quasi-static and fatigue performance of carbon fibre reinforced highly polymerized thermoplastic epoxy
    Hironori Nishida; Valter Carvelli; Toru Fujii; Kazuya Okubo
    Composites Part B: Engineering, Elsevier Ltd, 144 163 - 170, 01 Jul. 2018, Scientific journal
  • 廃棄プリプレグから抽出した再生炭素繊維のPPとの造粒時の折損 -成形複合材料の強度変化に及ぼす影響-
    大窪和也, 藤井 透, 糸川幸輝
    材料, 67(4) 424 - 429, Apr. 2018, Scientific journal
  • 竹から散りだした繊維を複合材料の強化材として使う
    藤井透; 大窪和也; 小武内 清貴; wenpeng Yu; Wenbin Yao
    JATAFFジャーナル, 6(8) 36 - 43, 19 Mar. 2018
  • The effect of microfibrils cellulose modified epoxy on the quasi-staticand fatigue behaviour of open holecarbon textile composites
    Valter Carvelli; Toru Fujii; Kazuya Okubo
    Journal of Composite Materials, 52(24) 3365 - 3380, 19 Mar. 2018, Scientific journal
  • 金属Vベルトを用いたCVTのトルク変動下での動力伝達
    磯峙 悠介, 大窪 和也, 藤井 透, 坂上 恭平, 矢ヶ崎 徹
    自動車技術会論文集, 49(6) 1230 - 1236, Mar. 2018, Scientific journal
  • Effective diameter of added glass fiber into matrix of carbon fiber reinforced thermo-plastics for improving mechanical properties
    Naoto Miyakita; Kazuya Okubo; Kiyotaka Obunai; Kazuya Yanagita
    33rd Technical Conference of the American Society for Composites 2018, 5 3042 - 3048, 2018, International conference proceedings
  • Improvement of Interfacial Adhesion Strength and MechanicalProperties of CFRP by Fabricated with Modified Matrix byAdding Nano Fibers
    HAYASHI Kenta; OKUBO Kazuya; OBUNAI Kiyotaka
    Journal of The Adhesion Society of Japan, The Adhesion Society of Japan, 54(11) 402 - 409, 2018
  • Breakages of recycled carbon fibers extracted from waste prepreg at pelletizing with PP - Its influence on strength of molded composite
    Kazuya Okubo; Toru Fujii; Koki Itokawa
    Zairyo/Journal of the Society of Materials Science, Japan, Society of Materials Science Japan, 67(4) 424 - 429, 2018, Scientific journal
  • Slip behavior in pulley groove up to sliding slip at steady state and power transmitting efficiency on metal V-belt type cvt
    Ryohei Okuda; Kazuya Okubo; Toru Fujii; Kyohei Sakagami; Toru Yagasaki
    Journal of Advanced Mechanical Design, Systems and Manufacturing, Japan Society of Mechanical Engineers, 11(6) 217 - 226, 01 Nov. 2017, International conference proceedings
  • Reduction of Maximum Torque of Driving Shafts Concurrently Driven by Rubber V-belt for Monorail Traveling on Worn Rack Rail for Construction Uses
    Kohei Nagao; Kazuya Okubo; Toru Fujii; Shoji Uchida
    International Journal of Materials, Mechanics and Manufacturing, Vol.5, No.3, August 2017, 5(3) 196 - 199, Aug. 2017
  • Improvement of Bending Strength of Carbon Fiber/Thermoplastic Epoxy Composites ?Effects of Molecular Weight of Epoxy on Carbon Fiber/Matrix Interfacial Strength and Connection of Cracks in Matrix
    Hironori Nishida; Kazuya Okubo; Toru Fujii; Valter Carvelli
    Open Journal of Composite Materials, 207 - 217, 27 Jul. 2017
  • 高分子量化した熱可塑性エポキシを母材とするCFRTPの機械的特性
    Hironori NISHIDA; Keisuke NAGAI; Kazuya OKUBO; Toru FUJII; Hiroshima Prefectural Technology Research Institute Doshisha University Graduate School of Science; Engineering
    強化プラスチック2017年6月号, 強化プラスチック協会, 63(6) 290 - 296, Jun. 2017
  • Influence of heating time of pyrolysis method for extracting recycled carbon fibers from wasted Prepreg on fiber breakages in its injection molded composite
    Koki Itokawa; Kazuya Okubo; Toru Fujii
    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2017, SPIE-INT SOC OPTICAL ENGINEERING, 10165, 2017, International conference proceedings
  • Effect of physical modification of matrix by nano(polyvinyl alcohol) fibers on fatigue performance of carbon fiber fabric-reinforced vinylester composites
    Yongzheng Shao; Kazuya Okubo; Toru Fujii; Ou Shibata; Yukiko Fujita
    JOURNAL OF COMPOSITE MATERIALS, SAGE PUBLICATIONS LTD, 50(29) 4065 - 4075, Dec. 2016, Scientific journal
  • Cement mortar reinforced with reclaimed carbon fibres, CFRP waste or prepreg carbon waste
    Hoang Nguyen; Valter Carvelli; Toru Fujii; Kazuya Okubo
    CONSTRUCTION AND BUILDING MATERIALS, ELSEVIER SCI LTD, 126 321 - 331, Nov. 2016, Scientific journal
  • A new unidirectional carbon fiber prepreg using physically modified epoxy matrix with cellulose nano fibers and spread tows
    Ryo Umeki; Aya Tanaka; Kazuya Okubo; Toru Fujii; Kazumasa Kawabe; Keiichi Kondo; Takeshi Yamazaki; Kenichi Hamada; Tetsuya Harada
    COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, ELSEVIER SCI LTD, 90 400 - 409, Nov. 2016, Scientific journal
  • Extracting condition of carbon fibers recycled from waste CFRP - Appropriate temperature condition in extraction for injection molded polypropylene composite
    Kazuya Okubo; Toru Fujii; Shota Nagata
    Zairyo/Journal of the Society of Materials Science, Japan, Society of Materials Science Japan, 65(8) 580 - 585, 01 Aug. 2016, Scientific journal
  • Mechanical characteristics of C/C composites modeified with micro-sized glass fibers
    Yasuhiro Utsunomiya; Kiyotaka Obunai; Tadao Fukuta; Koichi Ozaki; Kazuya Okubo; Toru Fujii
    Advanced Experimantal Mechanics, 1 126 - 130, Aug. 2016, Scientific journal
  • High pressure strength of carbon fibre reinforced vinylester and epoxy vessels
    Yongzheng Shao; Andrea Betti; Valter Carvelli; Toru Fujii; Kazuya Okubo; Ou Shibata; Yukiko Fujita
    COMPOSITE STRUCTURES, ELSEVIER SCI LTD, 140 147 - 156, Apr. 2016, Scientific journal
  • Repair of flexuously impact damaged CFRTP applying an inserting method with tiny melted sheet of PP resin modified with fine glass fibers
    Ryohei Ootani; Kazuya Okubo; Toru Fujii
    Key Engineering Materials, Trans Tech Publications Ltd, 705 108 - 113, 2016, International conference proceedings
  • Influence of locational states of submicron fibers added into matrix on mechanical properties of plain-woven carbon fiber composite
    Soichiro Kumamoto; Kazuya Okubo; Toru Fujii
    Curved and Layered Structures, De Gruyter Open Ltd, 3(1) 91 - 95, 01 Jan. 2016, Scientific journal
  • Improvement of fatigue life and prevention of internal crack initiation of chopped carbon fiber reinforced plastics modified with micro glass fibers
    Ryohei Fujitani; Kazuya Okubo; Toru Fujii
    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2016, SPIE-INT SOC OPTICAL ENGINEERING, 9800, 2016, International conference proceedings
  • Effects of Heat Treatment on the Mechanical Properties of Kenaf Fiber
    Paulo Teodoro D. L. Carada; Toru Fujii; Kazuya Okubo
    VIII INTERNATIONAL CONFERENCE ON TIMES OF POLYMERS AND COMPOSITES: FROM AEROSPACE TO NANOTECHNOLOGY, AMER INST PHYSICS, 1736, 2016, International conference proceedings
  • Improvement of Frictional Coefficient of Modified Shoe Soles onto Icy and Snowy Road by Tilting of Added Glass Fibers into Rubber
    Shunya Wakayama; Kazuya Okubo; Toru Fujii; Daisuke Sakata; Noriyuki Kado; Hiroshi Furutachi
    International Journal of Chemical, Molecular, materials and Metallurgical Engineering, 9(12) 1265 - 1269, Dec. 2015
  • Leak prevention of nitrogen gas for plain woven CF/epoxy composites by filling nanofiller under cryothermal fatigue
    Minoru Tamiaki; Toru Fujii; Kazuya Okubo
    Zairyo/Journal of the Society of Materials Science, Japan, Society of Materials Science Japan, 64(9) 739 - 744, 01 Sep. 2015, Scientific journal
  • Effect of cellulose nano fiber (CNF) on fatigue performance of carbon fiber fabric composites
    Yongzheng Shao; Tomoya Yashiro; Kazuya Okubo; Toru Fujii
    COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, ELSEVIER SCI LTD, 76 244 - 254, Sep. 2015, Scientific journal
  • Mechanical and morphology properties of cellulose nanocomposites
    Mohamed H. Gabr; Kazuya Okubo; Torn Fujii
    Handbook of Polymer Nanocomposites. Processing, Performance and Application: Volume C: Polymer Nanocomposites of Cellulose Nanoparticles, Springer Berlin Heidelberg, 249 - 264, 01 Jan. 2015, In book
  • Improvement of Fatigue Life of Plain-woven CFRP Modified with Enhanced Matrix with Sub-micron Sized Glass Fibers
    Kazuya Okubo; Toru Fujii; Tsubasa Kondo
    DESIGN, MANUFACTURING AND APPLICATIONS OF COMPOSITES, DESTECH PUBLICATIONS, INC, 107 - 114, 2015, International conference proceedings
  • Effect of Natural Fiber Reinforced Polypropylene Composite Using Resin Impregnation
    Gibeop Nam; Nanqi Wu; Kazuya Okubo; Toru Fujii
    Agricultural Sciences, 5(13) 1338 - 1343, Nov. 2014
  • Study of Maleic Anhydride Grafted Polypropylene Effect on Resin Impregnated Bamboo Fiber Polypropylene Composite
    Gibeop Nam; Noboru Wakamoto; Kazuya Okubo; Toru Fujii
    Agricultural Sciences, 5(13) 1322 - 1328, Nov. 2014
  • Effect of matrix properties on the fatigue damage initiation and its growth in plain woven carbon fabric vinylester composites
    Yongzheng Shao; Kazuya Okubo; Toru Fujii; Ou Shibata; Yukiko Fujita
    COMPOSITES SCIENCE AND TECHNOLOGY, ELSEVIER SCI LTD, 104 125 - 135, Nov. 2014, Scientific journal
  • Thermal and mechanical properties of electrospun nano-celullose reinforced epoxy nanocomposites
    Mohamed H. Gabr; Nguyen T. Phong; Kazuya Okubo; Kiyoshi Uzawa; Isao Kimpara; Toru Fujii
    POLYMER TESTING, ELSEVIER SCI LTD, 37 51 - 58, Aug. 2014, Scientific journal
  • Study on Effect of Matrix Properties on Fatigue Damage Initiation of Woven Carbon Fabric Vinylester Composites
    Yongzheng Shao; Kazuya Okubo; Toru Fujii; Ou Shibata; Yukiko Fujita
    ENGINEERING AND MANUFACTURING TECHNOLOGIES, TRANS TECH PUBLICATIONS LTD, 541-542 243 - +, 2014, International conference proceedings
  • Effect of PVA treatment on specific flexural strength and modulus of stampable sheet fabricated with bamboo fibers
    Junko Koike; Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, Society of Materials Science Japan, 63(5) 394 - 399, 2014, Scientific journal
  • Synthesization of CNTs on pore surfaces in C/C composites and effect of CNTs on tribological characteristics
    Kiyotaka Obunai; Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, Society of Materials Science Japan, 63(5) 356 - 361, 2014, Scientific journal
  • Improvement of mechanical properties in bamboo maleic anhydride grafted polypropylene/polypropylene composite enhanced with resin impregnation method
    Gibeop Nam; Noboru Wakamoto; Kazuya Okubo; Toru Fujii
    Advanced Materials Research, Trans Tech Publications Ltd, 1051 250 - 255, 2014, International conference proceedings
  • High cycles fatigue damage of CFRP plates clamped by bolts for axial coupling joint with off-set angle during rotation
    Kazuaki Ooka; Kazuya Okubo; Toru Fujii; Shinichi Umeda; Masayuki Fujii; Tetsuya Sugiyama
    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2014, SPIE-INT SOC OPTICAL ENGINEERING, 9058, 2014, International conference proceedings
  • Improvement of interfacial adhesion in bamboo polymer composite enhanced with microfibrillated cellulose
    Kazuya Okubo; Toru Fujii
    Polymer Composites, Biocomposites, Wiley Blackwell, 3 317 - 329, 21 Oct. 2013, In book
  • EFFECT OF A PVA TREATMENT ON INTERFACIAL SHEAR STRENGTH BETWEEN RECYCLED CARBON FIBER AND PP
    Yoshikazu Maehata; Dai Phu Hyunh; Bui Chuong; Toru Fujii; Kazuya Okubo
    Journal of Science AND TECHNOLOGY, 51(5A) 342 - 349, Sep. 2013
  • Improved fracture toughness and fatigue life of carbon fiber reinforced epoxy composite due to incorporation of rubber nanoparticles
    Nguyen Tien Phong; Mohamed H. Gabr; Le Hoai Anh; Vu Minh Duc; Andrea Betti; Kazuya Okubo; Bui Chuong; Toru Fujii
    JOURNAL OF MATERIALS SCIENCE, SPRINGER, 48(17) 6039 - 6047, Sep. 2013, Scientific journal
  • Influence of fiber extraction and surface modification on mechanical properties of green composites with bamboo fiber
    Hyojin Kim; Kazuya Okubo; Toru Fujii; Kenichi Takemura
    Journal of Adhesion Science and Technology, 27(12) 1348 - 1358, 01 Jun. 2013, International conference proceedings
  • Enhancement of mechanical properties of carbon fabric/epoxy composites using micro/nano-sized bamboo fibrils
    Nguyen Tien Phong; Mohamed H. Gabr; Kazuya Okubo; Bui Chuong; Toru Fujii
    MATERIALS & DESIGN, ELSEVIER SCI LTD, 47 624 - 632, May 2013, Scientific journal
  • Improvement in the mechanical performances of carbon fiber/epoxy composite with addition of nano-(Polyvinyl alcohol) fibers
    Nguyen Tien Phong; Mohamed H. Gabr; Kazuya Okubo; Bui Chuong; Toru Fujii
    Composite Structures, 99(99) 380 - 387, May 2013, Scientific journal
  • Mechanical, thermal, and moisture absorption properties of nano-clay reinforced nano-cellulose biocomposites
    Mohamed H. Gabr; Nguyen T. Phong; Mohammad Ali Abdelkareem; Kazuya Okubo; Kiyoshi Uzawa; Isao Kimpara; Toru Fujii
    Cellulose, 20(2) 819 - 826, 2013, Scientific journal
  • Improvement of total regenerated energy by two motors considering initial speed-ratio of CVT in power-train during reducing speed of automotive
    Masahiro Itani; Kazuya Okubo; Toru Fujii
    Applied Mechanics and Materials, 291-294(291-294) 886 - 891, 2013, International conference proceedings
  • Study on the effect of matrix properties on the mechanical performanceof carbon fabric composites
    Yongzheng Shao; Nguyen T. Phong; Kazuya Okubo; Toru Fujii; Ou Shibata; Yukiko Fujita
    Advanced Materials Research, 646 38 - 43, 2013, International conference proceedings
  • A simple method for estimating the driving resistance of rubber conveyer belts by using a self-traveling roller
    Shinya Kinoshita; Kazuya Okubo; Toru Fujii
    Applied Mechanics and Materials, 330 274 - 278, 2013, International conference proceedings
  • Enhancement of mechanical properties of carbon fabric/epoxy composites using micro/nano-sized bamboo fibrils
    Nguyen Tien Phong; Mohamed H. Gabr; Kazuya Okubo; Bui Chuong; Toru Fujii
    Materials and Design, Elsevier Ltd, 47 624 - 632, 2013, Scientific journal
  • Fatigue Damage Evaluation of Plain Woven Carbon Fiber Reinforced Plastic (CFRP) Modified with MFC (Micro-Fibrillated Cellulose) by Thermo-Elastic Damage Analysis (TDA)
    Ryohei Aoyama; Kazuya Okubo; Toru Fujii
    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2013, SPIE-INT SOC OPTICAL ENGINEERING, 8689, 2013, International conference proceedings
  • EFFECT OF PVA TREATMENT ON FLEXURAL PROPERTIES OF STAMPABLE SHEET FABRICATED WITH BAMBOO FIBERS
    Junko Koike; Kazuya Okubo; Toru Fujii
    Vietnam Journal of Chemistry, 50(6A) 197 - 201, Dec. 2012
  • A STUDY ON EFFECT OF NANO POLY VINYL ALCOHOL FIBERS ON FIBERS ON MECHANICAL PROPERTIES OF CF/EP COMPOSITE
    Nguyen Tien Phong; Mohamed H Gabr; Kazuya Okubo; Bui Chuong; Toru Fujii
    Vietnam Journal of Chemistry, 50(6A) 189 - 196, Dec. 2012
  • Synthesization of CNT on Surface of C/C Composites to Stabilize the Coefficient of Friction through a Wide Environmental Temperature Range
    Kiyotaka Obunai; Kazuya Okubo; Toru Fujii
    Journal of Materials Science Research, 2(1) 15 - 22, Oct. 2012
  • Improvement of bending strength and fracture toughness of C/C composite by adding carbon particles with 3-dimensional web-like structures
    Kiyotaka Obunai; Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, 公益社団法人 日本材料学会, 61(5) 468 - 473, May 2012, Scientific journal
  • Fabrication of bamboo fiber paper with shellac and its effect on specific elastic modulus
    Shigeyuki Suzuki; Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, 60(5) 413 - 417, May 2011, Scientific journal
  • Surface generation for Makyoh magic-mirror by end-milling with digitally functioned CNC machining center and magnetic polishing
    AOYAMA Eiichi; HIROGAKI Toshiki; OKUBO Kazuya; OGAWA Keiji; SAWA Kazuya; OGAWA Sachiko; KAWAI Ryouhei
    Journal of the Japan Society for Abrasive Technology, The Japan Society for Abrasive Technology, 55(9) 540 - 545, 2011
  • Effect of different types of aramid fibres on mechanical and thermal properties of nano-cellulose composites for vehicle applications
    Mohamed H. Gabr; Kaho Matsuoka; Kazuya Okubo; Toru Fujii
    International Journal of Vehicle Noise and Vibration, 6(2-4) 118 - 129, Nov. 2010, Scientific journal
  • Improvement of Mechanical Properties of C/C composite by Addition of Carbonized MFC into Carbon Precursor
    Obunai Kiyotaka; Takeuchi Yasunori; Okubo Kazuya; Fujii Toru
    The science and engineering review of Doshisha University, 同志社大学, 51(3) 26 - 31, Oct. 2010
  • Brake Torque Variation on Wave Type Brake Disc for Motorcycles
    OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru; NAKATSUJI Tsuyoshi
    Transactions of the Society of Automotive Engineers of Japan, 自動車技術会, 40(4) 961 - 966, 25 Jul. 2009
  • Study on Pre-treatment of Bamboo Fibers and Kneading Conditions in Process of Bamboo Fiber Reinforced Study on Pre-treatment of Bamboo Fibers and Kneading Conditions in Process of Bamboo Fiber Reinforced Polypropylene by Twin Screw Extrusion
    Kim Hyojin; Kim Hyojin; Okubo Kazuya; Fujii Toru
    The science and engineering review of Doshisha University, Doshisha University, 50(2) [100] - 106, Jul. 2009
  • Effective degree of fibrillation of micro-fibrillated bamboo fiber processed by stone mill for improving mechanical properties of PLA composite
    Chiaki Tanaka; Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, 58(5) 368 - 373, May 2009, Scientific journal
  • Brake Torque Variation on Wave Type Brake Disc for Motorcycles
    OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru; NAKATSUJI Tsuyoshi
    Transactions of the Society of Automotive Engineers of Japan, 自動車技術会, 39(2) 63 - 66, 25 Mar. 2008
  • 1537 On how to reduce the fiber breakage during fabricating PP-based green composite pellets containing bamboo short fibers
    Kubota Hideoki; Fujii Toru; Okubo Kazuya; Tanaka Tatsuya; Fujiura Takayasu; Nagatani Asahiro
    The proceedings of the JSME annual meeting, The Japan Society of Mechanical Engineers, 2008 369 - 370, 2008
  • Study on Failure of Casing : Relationship Between Internal Structure (Cellulose Short Fibers/Collagen Composite) and Failure Strain
    IWAMOTO Hiroshi; OKUBO Kazuya; TANAKA Tatsuya; FUJII Toru; ITO Noriichi
    Transactions of the Japan Society of Mechanical Engineers Series B, The Japan Society of Mechanical Engineers, 73(734) 85 - 93, 25 Oct. 2007
  • ミクロフィブリル化竹繊維を用いた環境適応型材料 ―射出成形への応用―
    田中千晶; Vu Minh Duc; 大窪和也; 藤井 透
    BAMBOO JOURNAL, 竹文化振興協会, 124(24) 17 - 26, Mar. 2007
  • Study on low speed judder of wave type brake discs for motorcycles
    Kiyotaka Obunai; Kazuya Okubo; Toru Fujii; Tsuyoshi Nakatsuji
    SAE Technical Papers, SAE International, 13 Nov. 2006, International conference proceedings
  • Composites Science/Technology and New Challenges for Tomorrow's Applications : IV: Green Composites' Research and Today's Progress
    OKUBO Kazuya; TAKAGI Hitoshi; GODA Koichi
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 1(55) 438 - 444, Jan. 2006
  • Development of flexible sensor for assisting device at stand-up and sit-down motion
    Norio Nakagawa; Kazuya Okubo; Toru Fujii
    2006 INTERNATIONAL CONFERENCE ON ELECTRONIC MATERIALS AND PACKAGING, VOLS 1-3, IEEE, 777 - +, 2006, International conference proceedings
  • Evaluation of Fatigue Degradation with Configuration of Matrix Cracks for Plain-Woven CF/Epoxy Composites
    NISHIKAWA Yasuhiro; OKUBO Kazuya; FUJII Toru
    Transactions of the Japan Society of Mechanical Engineers Series B, The Japan Society of Mechanical Engineers, 71(705) 775 - 779, 25 May 2005
  • Fatigue Damage Evaluation of Plain-Woven Carbon/Epoxy Composites Using Thermo-Elastic Technique(The Frontier of Applications for Composite Materials)
    NISHIKAWA Yasuhiro; OKUBO Kazuya; FUJII Toru; UENOYA Toshiyuki
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 54(5) 494 - 499, 15 May 2005
  • 2113 Effective Fabricating Condition of Green Composite Using Microfibrillated Cellulose Extracted from Bamboo without Polymer Adhesive
    TAKAHASHI Nobuya; OKUBO Kazuya; FUJII Toru
    The proceedings of the JSME annual meeting, The Japan Society of Mechanical Engineers, 2005 535 - 536, 2005
  • Effect of Moisture Absorption during Fabrication Stage on Static and Fatigue Properties for Plain Woven CF/Epoxy Composite
    NISHIKAWA Yasuhiro; OKUBO Kazuya; FUJII Toru
    Transactions of the Japan Society of Mechanical Engineers Series B, The Japan Society of Mechanical Engineers, 70(697) 1319 - 1325, 25 Sep. 2004
  • The Bumping Mechanism of the GFRP-Skinned Sandwich Panel
    TAMIAKI Minoru; FUJII Toru; OKUBO Kazuya
    Journal of the Japan Society for Composite Materials, JAPAN SOCIETY FOR COMPOSITE MATERIALS, 30(5) 192 - 198, 15 Sep. 2004
  • Fatigue of Adhesive Bonded Joints and Structures
    FUJII Toru; OKUBO Kazuya
    Journal of The Adhesion Society of Japan, The Adhesion Society of Japan, 40(2) 66 - 73, 01 Feb. 2004
  • Fatigue Damage Progression of Woven Fabric Composites under Cyclic Loading : Observation of Initial Damage Process by Thermoelastic Image Technique
    NISHIKAWA Yasuhiro; OKUBO Kazuya; FUJII Toru; UENOYA Toshiyuki
    Transactions of the Japan Society of Mechanical Engineers Series B, The Japan Society of Mechanical Engineers, 70(689) 101 - 106, 25 Jan. 2004
  • Fractals of Fracture Surface of Adhesive Joints using Epoxy adhesives
    FUJII Toru; OKUBO Kazuya
    GOMU, THE SOCIRETY OF RUBBER SCIENCE AND TECHNOLOGYY, JAPAN, 77(2) 65 - 70, 2004
  • Permanent deflection of two-layered clutch plates - How to reduce the deflection of two-layered clutch plates
    Damien Costet; Toru Fujii; Kazuya Okubo; Shinya Oomori
    SAE Technical Papers, 2004, International conference proceedings
  • 竹繊維を用いた環境適合型複合材料
    藤井 透; 大窪和也
    繊維学会誌(繊維と工業), The Society of Fiber Science and Technology, Japan, 59(3) 12 - 15, 2003
  • Optimization of manufacturing process of glass fibers/phenol composites. effects of solidification conditions, fiber length and additional materials on their mechanical properties
    Pierre-Rene Houdart; Toru Fujii; Kazuya Okubo
    SAE Technical Papers, 2003, International conference proceedings
  • Influence of Hole Layout on Crack Initiation from Small Holes for One-Piece Brake Discs : Improvement Method for Crack Initiation
    SASADA Masahiro; NAKATSUJI Tsuyoshi; OKUBO Kazuya; FUJII Toru; KAMEDA Naganao
    Transactions of the Japan Society of Mechanical Engineers. Series C., The Japan Society of Mechanical Engineers, 68(673) 2797 - 2804, Sep. 2002
  • Effect of Pellet Geometry and Water Absorption on Strength of Long Jute Fiber Reinforced Polypropylene
    SHIMA Kazuhiro; MIZOGUCHI Hironori; OKUBO Kazuya; FUJII Toru; TANAKA Tatsuya
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 51(7) 826 - 831, 15 Jul. 2002
  • Effect of Swelling of Jute Fibers on Mechanical Properties of Jute Fiber Reinforced Plastics due to Water Absorption
    MIZOGUCHI Hironori; OKUBO Kazuya; FUJII Toru
    Proceedings of the 1992 Annual Meeting of JSME/MMD, The Japan Society of Mechanical Engineers, 2002 351 - 352, 2002
  • Effect of fiber length on the relationship between interfacial strength and tensile strength for jute fiber reinforced polypropylene
    SHIMA Kazuhiro; OKUBO Kazuya; FUJII Toru
    Proceedings of the 1992 Annual Meeting of JSME/MMD, The Japan Society of Mechanical Engineers, 2002 353 - 354, 2002
  • Effect of Fillets on the Tensile Shear Strength of Adhesively Bonded Joints
    FUJII Toru; OKUBO Kazuya; MATSUI Takashi
    Journal of The Adhesion Society of Japan, The Adhesion Society of Japan, 37(3) 109 - 118, 01 Mar. 2001
  • Static and fatigue crack propagation of toughened epoxy adhesives under Mixed Mode loading
    Kazuya Okubo; Hiroaki Yoshimitsu; Toru Fujii
    Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A, Japan Society of Mechanical Engineers, 67(661) 1514 - 1519, 2001, Scientific journal
  • Static and Fatigue Shear Characteristics of Rubber-Metal Laminated Bearings Partially Using High Tearing Rubber at Their Edge under Compression
    OKUBO Kazuya; KURODA Susumu; FUJII Toru
    GOMU, THE SOCIRETY OF RUBBER SCIENCE AND TECHNOLOGYY, JAPAN, 73(9) 511 - 517, 15 Sep. 2000
  • Low-cycle fatigue of stainless steel under cyclic compression
    NAKATSUJI Tsuyoshi; SASADA Masahiro; OKUBO Kazuya; FUJII Toru
    Proceedings of the 1992 Annual Meeting of JSME/MMD, The Japan Society of Mechanical Engineers, 2000 423 - 424, 2000
  • Study on crack initiation from holes of one-piece brake disk for motor bicycles
    Sasada Masahiro; Nakatsuji Tuyoshi; Okubo Kazuya; Fujii Toru; Kameda Naganao
    Proceedings of the 1992 Annual Meeting of JSME/MMD, The Japan Society of Mechanical Engineers, 2000 661 - 662, 2000
  • Study on Crack Initiation from Small Holes of One-Piece Brake Disks for Motorcycles (How Braking Torque Directly Affects the Crack Initiation ?)
    Masahiro Sasada; Kazuya Okubo; Toru Fujii; Naganao Kameda
    Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C, 66(646) 2016 - 2023, 2000, Scientific journal
  • Surface flaws of glass fiber - their size and distribution
    Kazuya Okubo; Toru Fujii
    Zairyo/Journal of the Society of Materials Science, Japan, Soc Mater Sci, Japan, 49(7) 819 - 824, 2000, Scientific journal
  • Effect of Edge Shape on Static and Fatigue Failure of Steel-Rubber Laminated Structure in Shear with Compression
    OKUBO Kazuya; LEE Yi-Chang; KURODA Susumu; FUJII Toru
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 48(9) 1017 - 1021, 15 Sep. 1999
  • Strength of Hole Notched Composite under Tension-Torsion Biaxiially Combined Static Load
    AMIJIMA Sadao; FUJII Toru; OKUBO Kazuya; KATAYAMA Yuji
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 41(464) 673 - 679, 15 May 1992
  • Effect of Textural Pitch on Static Strength of Hole Notched Woven Glass Composite
    AMIJIMA Sadao; FUJII Toru; OKUBO Kazuya; MATSUOKA Toshihiro
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 41(464) 668 - 672, 15 May 1992
  • Effect of Biaxiality Ratio under Combined Stress on Fatigue Notch Factor in Composites with a Hole.
    AMIJIMA S.; FUJII T.; OKUBO K.; SHINA T.
    Journal of the Japan Society for Composite Materials, JAPAN SOCIETY FOR COMPOSITE MATERIALS, 18(1) 10 - 16, 1992
  • 平織りガラス繊維強化積層板の微視的疲労損傷メカニズム
    Kazuya OKUBO
    日本複合材料学会誌, JAPAN SOCIETY FOR COMPOSITE MATERIALS, 16(6) 241 - 247, Nov. 1990
  • Influence of Environmental Temperature on Fatigue Property of Center Hole Notched GFRP Reinforced by Plain Woven Glass Cloth
    AMIJIMA Sadao; FUJII Toru; OHKUBO Kazuya; MATSUOKA Toshihiro
    Journal of the Society of Materials Science, Japan, The Society of Materials Science, Japan, 39(441) 706 - 710, 15 Jun. 1990

MISC

  • 炭素繊維/樹脂間の界面接着せん断強度に及ぼす繊維表面のサイジング処理効果の負荷ひずみ速度の違いによる変化—Change in Effects of Sizing Treatment on Interfacial Shear Strength between Carbon Fiber and Resin According to Difference of Loading Strain Rate
    村山 凌太郎; 小武内 清貴; 大窪 和也
    日本接着学会誌 = Journal of the Adhesion Society of Japan : adhesion, 日本接着学会, 59(3) 65 - 72, 2023
  • Influence of Deformation of Elements in Width Direction on Winding Radial Displacement in Pulley Groove of Metal V-belt Type CVT
    三林誠治; 八幡樹; 小武内清貴; 大窪和也
    自動車技術会論文集(Web), 53(6), 2022
  • 竹繊維の利活用 : その可能性を探る (天然素材関連特集)
    藤井 透; 大窪 和也; 小武内 清貴
    強化プラスチックス, 強化プラスチック協会, 67(8) 329 - 335, Aug. 2021
  • Improvement of Interfacial Properties and Fatigue Life by High Polarization of Epoxy Matrix of CFRP
    松田 遼亮; 小武内 清貴; 大窪 和也; 河村 奈緒
    強化プラスチックス, 強化プラスチック協会, 66(1) 30 - 35, Jan. 2020
  • 産業用ベルト伝動の基礎と伝動設計 (特集 動力伝達技術)
    大窪 和也; 小武内 清貴
    月刊トライボロジー, 新樹社, 33(12) 39 - 41, Dec. 2019
  • セルロースナノファイバー(CNF)の添加によるCFRPの疲労寿命の改善事例 (セルロースナノファイバー関連特集)
    大窪 和也; 小武内 清貴; 田中 亜弥
    強化プラスチックス, 強化プラスチック協会, 65(11) 462 - 465, Nov. 2019
  • 炭素繊維のリサイクルと問題点 (CFRPリサイクル特集)
    藤井 透; 大窪 和也
    強化プラスチックス, 強化プラスチック協会, 63(5) 226 - 232, May 2017
  • 衝撃曲げ損傷を受けたCFRTPの補修技術の紹介 : 微細ガラス繊維添加改質小片を用いる手法の検討
    大窪 和也; 藤井 透; 大谷 龍平
    強化プラスチックス, 強化プラスチック協会, 63(4) 175 - 180, Apr. 2017
  • Change in Interfacial Shear Strength with Carbon Fiber According to Difference of Molecular Weight of Thermoplastic Epoxy
    西田 裕紀; 永井 奎祐; 大窪 和也; 藤井 透
    日本接着学会誌 = Journal of the Adhesion Society of Japan : adhesion, 日本接着学会, 53(11) 375 - 380, 2017
  • Shear Strength between PP Resin and Recycled Carbon Fiber Extracted from Wasted Prepreg : Change of Interfacial Shear Strength Measured by Micro Drop Let Test with Recycled Extraction Condition
    糸川 幸輝; 大窪 和也; 藤井 透
    日本接着学会誌 = Journal of the Adhesion Society of Japan : adhesion, 日本接着学会, 53(6) 210 - 216, 2017
  • Moderation in Temperature Dependence of Counter Frictional Coefficient and Prevention of Wear of C/C composites by Synthesizing SiC on Surface and internal Vacancies
    WAKAMOTO Noboru; OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru
    The Proceedings of Conference of Kansai Branch, 一般社団法人 日本機械学会, 2017(0), 2017
  • Fatigue and Failure of Advanced Composite Material
    大窪 和也; 藤井 透
    成形加工 = Journal of the Japan Society of Polymer Processing : プラスチック成形加工学会誌, プラスチック成形加工学会, 28(9) 357 - 361, Sep. 2016
  • M704 Effect of addition of Cellulose Nanofibers (CNFs) on mechanical properties of CFRP : Verification of stress state around CNF added into matrix by FEM
    HAYASHI Sachie; OKUBO Kazuya; FUJII Toru
    関西支部講演会講演論文集, The Japan Society of Mechanical Engineers, 2016(91) 314 - 314, 11 Mar. 2016
  • Effect of Needle Punching on Flexural Properties of Stampable Sandwich Sheet Fabricated with Bamboo Fiber and Recycled Carbon Fiber MAT
    大窪 和也; 藤井 透
    機能材料, シーエムシー出版, 36(2) 48 - 56, Feb. 2016
  • Why Recycling Carbon Fibers and How Promoting its Business!
    藤井 透; 大窪 和也
    成形加工 = Journal of the Japan Society of Polymer Processing : プラスチック成形加工学会誌, プラスチック成形加工学会, 27(12) 497 - 502, Dec. 2015
  • Recycling of Carbon Fiber and CFRP
    Toru Fujii; Kazuya Okubo
    SEN-I GAKKAISHI, SOC FIBER SCIENCE TECHNOLOGY, 71(11) 535 - 546, Nov. 2015, Book review
  • 天然繊維を用いた複合材料(グリーンコンポジット)の10年の歩み (FRP60年の歩み)
    藤井 透; 大窪 和也
    強化プラスチックス, 強化プラスチック協会, 61(8) 402 - 410, Aug. 2015
  • Cyclic bending fatigue property of piled CFRP plates subjected to out-plane bending under high humidity conditions
    尾崎 功一; 大窪 和也; 藤井 透
    強化プラスチックス, 強化プラスチック協会, 60(12) 511 - 513, Dec. 2014
  • OS1728 Moderation of Dependence of Frictional Coefficient of C/C Composite on Temperature due to Addition of Glass Fibers into Carbon Precursor
    FUJITANI Ryohei; OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru
    M&M材料力学カンファレンス, The Japan Society of Mechanical Engineers, 2014 "OS1728 - 1"-"OS1728-3", 19 Jul. 2014
  • 再生炭素繊維を用いたCFRTP射出成形品の機械的特性に及ぼすPVA処理の効果
    永田 章太; 大窪 和也; 藤井 透
    強化プラスチックス, 強化プラスチック協会, 60(4) 125 - 129, Apr. 2014
  • Boost Up the Carbon Fiber Recycling Business Now : It's Not Too Early, But Not Too Late
    藤井 透; 大窪 和也
    機能材料, シーエムシー出版, 33(12) 41 - 50, Dec. 2013
  • Classification of Recycled Carbon Fibers in Consideration of their Applications and Handling of CFRP Waste
    藤井 透; 大窪 和也
    機能材料, シーエムシー出版, 33(11) 59 - 65, Nov. 2013
  • OS1926 Influence of impact velocity of small projectile on absorbing property of CFRP/ceramic sandwich plate
    SHINOMIYA Masatsugu; OKUBO Kazuya; FUJII Toru
    M&M材料力学カンファレンス, The Japan Society of Mechanical Engineers, 2013 "OS1926 - 1"-"OS1926-3", 12 Oct. 2013
  • Recycling of CFRP, Now
    藤井 透; 大窪 和也
    機能材料, シーエムシー出版, 33(10) 54 - 59, Oct. 2013
  • 海外情報 ベトナムにおけるFRP事情
    藤井 透; 大窪 和也; VuMinhDuc
    強化プラスチックス, 強化プラスチック協会, 59(9) 337 - 342, Sep. 2013
  • How to Use Natural Plant Fibers, Property? : Use of Bamboo Fibers as the Third Sustainable Fiber Substituting for Glass Fiber and Their Applications
    藤井 透; 大窪 和也
    成形加工 = Journal of the Japan Society of Polymer Processing : プラスチック整形加工学会誌, プラスチック成形加工学会, 25(3) 119 - 124, Mar. 2013
  • Fabrication Method and Strength Properties of Bamboo Fiber Reinforced Composite
    TAMIAKI Minoru; FUJII Toru; OKUBO Kazuya; ITO Norihito
    Memoirs of Suzuka College of Technology, Suzuka National College of Technology, 46 17 - 22, 28 Feb. 2013
  • 604 Improvement of fatigue property of loop joint for braided steel wire in its rubber composite with damage detecting system
    SAKATA Yuki; OKUBO Kazuya; FUJII Toru; AMANO Shigehiko; Hou Gang
    関西支部講演会講演論文集, The Japan Society of Mechanical Engineers, 2012(87) "6 - 4", 16 Mar. 2012
  • 501 Simple evaluation with self-traveling roller to determine driving resistance of rubber conveyor belt
    KINOSHITA Shinya; OKUBO Kazuya; FUJII Toru
    学術講演会講演論文集, 日本材料学会, 61 103 - 104, 2012
  • Study on How to Effectively Extract Bamboo Fibers From Raw Bamboo and Wastewater Treatment
    Kazuya Okubo
    Journal of Materials Science Research, 1(1) 144 - 155, 2012
  • 428 Improvement of Fatigue Life of CFRP Pipe Modified with Micro Fibrillated CelluloseSubjected to Cyclic Impact Loading
    UEMATSU Shunichi; OKUBO Kazuya; FUJII Toru
    関西支部講演会講演論文集, The Japan Society of Mechanical Engineers, 2011(86) "4 - 28", 19 Mar. 2011
  • Can nano-fibers (MFC) fibers extracted from biomass resources extend the fatigue life of carbon fabric composites?
    藤井 透; 大窪 和也
    The Science and engineering review of Doshisha University, 同志社大学理工学研究所, 51(4) 105 - 110, Jan. 2011
  • 424 Improvement of Coefficient of Friction between C/C Composites
    OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru
    The Proceedings of Conference of Kansai Branch, The Japan Society of Mechanical Engineers, 2011(0) _4 - 24_, 2011
  • Modeling of Stiffness Reduction of Vibration Conveyor Springs Subjected to Ultra High Cyclic Loading under High Humidity
    Takahiko Yoshi; Kazuya Okubo; Toru Fujii
    COMPOSITE SCIENCE AND TECHNOLOGY, PTS 1 AND 2, TRANS TECH PUBLICATIONS LTD, 471-472 975 - 980, 2011
  • Synthesization of CNT on surface of C/C composites by alcohol CVD method and its effect on coefficient of friction between them
    K. Obunai; K. Okubo; T. Fujii
    25th Technical Conference of the American Society for Composites and 14th US-Japan Conference on Composite Materials 2010, 1 711 - 720, 01 Dec. 2010
  • A study on mechanical properties of bacterial cellulose/epoxy reinforced by plain woven carbon fiber modified with liquid rubber
    Mohamed H. Gabr; Mostafa Abd Elrahman; Kazuya Okubo; Toru Fujii
    COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, ELSEVIER SCI LTD, 41(9) 1263 - 1271, Sep. 2010
  • Effect of microfibrillated cellulose on mechanical properties of plain-woven CFRP reinforced epoxy
    Mohamed H. Gabr; Mostafa Abd Elrahman; Kazuya Okubo; Toru Fujii
    COMPOSITE STRUCTURES, ELSEVIER SCI LTD, 92(9) 1999 - 2006, Aug. 2010
  • Interfacial adhesion improvement of plain woven carbon fiber reinforced epoxy filled with micro-fibrillated cellulose by addition liquid rubber
    Mohamed H. Gabr; Mostafa Abd Elrahman; Kazuya Okubo; Toru Fujii
    JOURNAL OF MATERIALS SCIENCE, SPRINGER, 45(14) 3841 - 3850, Jul. 2010
  • 518 Destruction of Steel Wire and Cover Gum of Conveyer Belt Under Repeated Impact Load
    中村 知尋; 大窪 和也; 藤井 透; 天野 成彦; 侯 剛
    関西支部講演会講演論文集, The Japan Society of Mechanical Engineers, 2010(85) "5 - 18", 16 Mar. 2010
  • G04002-5 Improvement of mechanical properties of carbon fiber reinforced carbon composites by addition of Carbonized MFC into carbon precursor
    TAKEUCHI Yasunori; OBUNAI Kiyotaka; OKUBO Kazuya; FUJII Toru; NAKATSUJI Tsuyshi
    The proceedings of the JSME annual meeting, The Japan Society of Mechanical Engineers, 2010(0) 363 - 364, 2010
  • Stiffness reduction of woven CFRP and CFRTP spring under ultra high cyclic fatigue for vibration conveyor
    Takahiko Yoshi; Kazuya Okubo; Toru Fujii
    MULTI-FUNCTIONAL MATERIALS AND STRUCTURES III, PTS 1 AND 2, TRANS TECH PUBLICATIONS LTD, 123-125 217 - +, 2010
  • Modification of strain distribution on contact surface of shoe to reduce low frequency squeals for brake disc with small holes
    Kiyotaka Obunai; Sho Hagiwara; Kazuya Okubo; Toru Fujii; Tsuyoshi Nakatsuji
    SAE Technical Papers, 2010-01-1715, 2010
  • Calculation of Fuel Consumption on Hybrid Power System Driven by Two Motors Connected in Series with CVT
    Koji Sakota; Kazuya Okubo; Toru Fujii
    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTISTS (IMECS 2010), VOLS I-III, INT ASSOC ENGINEERS-IAENG, 1136 - +, 2010
  • Multi-scale hybrid biocomposite: Processing and mechanical characterization of bamboo fiber reinforced PLA with microfibrillated cellulose
    Kazuya Okubo; Toru Fujii; Erik T. Thostenson
    COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, ELSEVIER SCI LTD, 40(4) 469 - 475, Apr. 2009
  • Crack initiation and propagation mode of CFRP pipe under cyclic three point impact bending
    高垣 宜史; 大窪 和也; 藤井 透
    JCOM講演論文集, [日本材料学会], 38 280 - 283, 10 Mar. 2009
  • Improvement in specific elastic modulus of paper fabricated with bamboo single fibers with shellac
    鈴木 茂之; 大窪 和也; 藤井 透
    JCOM講演論文集, [日本材料学会], 38 9 - 12, 10 Mar. 2009
  • Improvement in specific elastic modulus of paper fabricated with bamboo fibers by addition of natural shellac
    鈴木 茂之; 大窪 和也; 藤井 透
    Bamboo journal, 竹文化振興協会, (26) 11 - 16, Mar. 2009
  • 420 Mechanical and thermal properties of compressed cellulose reinforced by entangled micro-fibrillated aramid fiber
    WAKASUGI Keisuke; OKUBO Kazuya; FUJII Toru
    学術講演会講演論文集, 日本材料学会, 58 303 - 304, 2009
  • Characterization of Colloquium & Exhibition Wave Type Brake Disc for Motorcycles
    SAE 2009 Annual Brake Colloquium & Exhibition, 107 - 111, 2009
  • Characterization of brake torque variation of wave type brake disc for motorcycles
    Kiyotaka Obunai; Kazuya Okubo; Toru Fujii; Tsuyoshi Nakatsuji
    SAE Technical Papers, 107 - 111, 2009
  • Belt penetration and local slip in the pulley groove for metal V-belt CVT (Continuously Variable Transmission) at steady state
    Conference: IAMF 2009, 2009
  • Effective control of pulley thrusts using an index describing belt slip state in metal V-belt type CVT for improving transmitting efficiency
    坂上 恭平; 大窪 和也; 藤井 透
    Transactions of the Society of Automotive Engineers of Japan, 自動車技術会, 39(5) 101 - 106, Sep. 2008
  • Development of pleasure boat reinforced by non-woven cloth of compressed bamboo fiber dried by far infrared rays
    田中 隆介; 大窪 和也; 藤井 透
    JCOM講演論文集, [日本材料学会], 37 121 - 125, 18 Mar. 2008
  • Prediction of mechanical properties of a randomly oriented short bamboo fibers reinforced plastic (JCOM-37 プログラム--材料・構造の複合化と機能化に関するシンポジウム)
    Colombet Antoine; 藤井 透; 大窪 和也
    JCOM講演論文集, [日本材料学会], 37 143 - 147, 18 Mar. 2008
  • Effect of dispersion process of enhancing cellulose on fracture behavior around reinforcement in epoxy and PLA/bamboo fiber composites (第46回 同志社大学理工学研究所研究発表会 2007年度 同志社大学ハイテク・リサーチ,学術フロンティア合同シンポジウム)
    大窪 和也; 藤井 透
    同志社大学理工学研究報告, 同志社大学理工学研究所, 48(4) 59 - 64, Jan. 2008
  • Effect of surface Treatment with sodium hydroxide and Silane Coupling Agent on the Mechanical Properties of Bamboo fiber Composites
    50(2) 90 - 95, 2008
  • Effect of surface treatment and addition of micro fibrillated bamboo fiber on mechanical properties of loudspeaker diaphragm
    The IUMRS International Conference in Asia, 2008
  • APPLICATION OF HIGH HOMOGENIZATION TECHNIQUE TO FABRICATION OF ELECTRIC TESTING PROVE DISK USING MICRO-FIBRILLATED BACTERIA CELLULOSE
    the Third International Conference on Material and Processing, 2008
  • Effect of surface Treatment of Bamboo Fiber with Sodium Hydroxide and Silane Coupling agent on Mechanical Properties of Its Composites
    The 6th Asian-Australasian Conference on Composite Materials, 215 - 218, 2008
  • Fatigue and impact properties of plain-woven CFRP modified with Micro Fibrillate Cellulose
    The 6th Asian-Australasian Conference on Materials, 449 - 501, 2008
  • Improvement of fatigue strength and impact properties of plain-woven CFRP modified with Micro Fibrillated Cellulose
    Norifumi Takagaki; Kazuya Okubo; Toru Fujii
    MULTI-FUNCTIONAL MATERIALS AND STRUCTURES, PTS 1 AND 2, TRANS TECH PUBLICATIONS LTD, 47-50(50) 133 - 136, 2008
  • High Homogenization Technique for Micro-fibrillated bacteria Cellulose to Fabricate electric testing prove Disk
    Proceedings of International Workshop on Green Composites 5, 4 71 - 76, 2008
  • Improvement in the mechanical properties of light curing epoxy resin with MFC(Micro-Fibrillated Cellulose)
    Y. Ohnishi; T. Fujii; K. Okubo
    HIGH PERFORMANCE STRUCTURES AND MATERIALS IV, WIT PRESS/COMPUTATIONAL MECHANICS PUBLICATIONS, 97 139 - +, 2008
  • Development of high strength bamboo paper using parenchyma cells
    S. Suzuki; K. Okubo; T. Fujii
    HIGH PERFORMANCE STRUCTURES AND MATERIALS IV, WIT PRESS/COMPUTATIONAL MECHANICS PUBLICATIONS, 97 241 - +, 2008
  • How to improve mechanical properties of polylactic acid with bamboo fibers
    Ryoko Tokoro; Duc Minh Vu; Kazuya Okubo; Tatsuya Tanaka; Toru Fujii; Takayasu Fujiura
    JOURNAL OF MATERIALS SCIENCE, SPRINGER, 43(2) 775 - 787, Jan. 2008
  • グリーンコンポジット 現状と将来展望 (再生・持続可能エネルギーとFRP特集)
    大窪 和也; 藤井 透
    強化プラスチックス, 強化プラスチック協会, 53(11) 487 - 492, Nov. 2007
  • How to Apply Polymer Matrix Composites (PMC) Using Natural Plant Fibers to Automobiles
    FUJII Toru; OKUBO Kazuya
    自動車技術 = Journal of Society of Automotive Engineers of Japan, 自動車技術会, 61(10) 83 - 90, 01 Oct. 2007
  • 最近の伝動ベルトの技術動向--平ベルト伝動を見直そう (主要機械要素選定ガイド2007) -- (伝動ベルト編)
    藤井 透; 大窪 和也
    機械設計, 日刊工業新聞社, 51(6) 36 - 39, Apr. 2007
  • Study on Crack Initiation from Small Holes Opened in Brake Disc for Motor Cycles
    NAKATSUJI Tsuyoshi; YUASA Hitoshi; OKUBO Kazuya; FUJII Toru
    Transactions of the Japan Society of Mechanical Engineers C, The Japan Society of Mechanical Engineers, 73(727) 825 - 832, 25 Mar. 2007
  • Improvement of mechanical properties of composite based on light curing optical epoxy resin reinforced by MFC (Micro-Fibrillated Cellulose)
    大西 遊理; 大窪 和也; 藤井 透
    JCOM講演論文集, [日本材料学会], 36 169 - 173, 08 Mar. 2007
  • Effect of Initial Residual Stress to Crack Initiation on Brake Disc for Motorcycles
    Nakatsuji Tsuyoshi; Koyama Yoshihiro; Ookubi Kazuya; Fujii Toru
    The science and engineering review of Doshisha University, Doshisha University, 47(4) 216 - 222, Jan. 2007
  • Effect of initial residual stress on crack initiation from tiny holes of brake discs for motorcycles
    Yoshihiro Koyama; Kazuya Okubo; Toru Fujii; Tsuyoshi Nakatsuji
    SAE Technical Papers, 2141 - 2147, 2007
  • Crack Initiation around Small Holes of One-piece Brake Discs under Cyclic Heat Condition
    JSMS, 73(727) 825 - 832, 2007
  • Fatigue crack constraint in plain-woven CFRP using newly-developed spread tows
    Yasuhiro Nishikawa; Kazuya Okubo; Toru Fujii; Kazumasa Kawabe
    INTERNATIONAL JOURNAL OF FATIGUE, ELSEVIER SCI LTD, 28(10) 1248 - 1253, Oct. 2006
  • Effect of Frictional Force Distribution on Exciting Force of Brake Noise for Motorcycle Disk Brake
    NAKATSUJI Tsuyoshi; ODA Naoto; OKUBO Kazuya; FUJII Toru
    Transactions of the Japan Society of Mechanical Engineers C, The Japan Society of Mechanical Engineers, 72(721) 3016 - 3021, 25 Sep. 2006
  • Damage Distribution and Damage Progression Behavior of Plain Woven CF/Epoxy Composites under Cyclic Loading
    HIRATA Satoshi; OKUBO Kazuya; FUJII Toru; NISHIKAWA Yasuhiro
    Journal of JSEM, 日本実験力学会, 6(2) 145 - 151, 25 Jun. 2006
  • 研究室紹介(1)同志社大学工学部 構造工学研究室
    藤井 透; 大窪 和也
    強化プラスチックス, 強化プラスチック協会, 52(5) 234 - 236, May 2006
  • 1202 Effect of internal structure factors on breaking strain of food grade film which consists of cellulose/collagen
    IWAMOTO Hiroshi; OKUBO Kazuya; Fujii Toru; ITO Norikazu
    関西支部講演会講演論文集, The Japan Society of Mechanical Engineers, 2006(81) "12 - 2", 17 Mar. 2006
  • 竹繊維と環境 (特集欄 環境調和型機械材料と材料加工) -- (加工技術編)
    藤井 透; 大窪 和也
    機械の研究, 養賢堂, 58(1) 214 - 221, Jan. 2006
  • カーボンナノチューブとミクロフィブリルセルロースによる光硬化エポキシ樹脂の強化とその特性 (別冊 第43回同志社大学理工学研究所研究発表会,2005年度同志社大学ハイテク・リサーチ,学術フロンティア合同シンポジウム講演予稿集〔含 当日配付資料〕)
    藤井 透; 大窪 和也; 上甲 圭悟
    同志社大学理工学研究報告, 同志社大学理工学研究所, 46(4) 112 - 116, Jan. 2006
  • On the Several factors Affecting Mannual Clutch Judder
    He Hanjun; Okubo kazuya; Fujii Toru
    The science and engineering review of Doshisha University, Doshisha University, 47(2) 1 - 9, 2006
  • Fatigue Behavior of Plain Woven CF/Epoxy Composites using Spread Tow
    Experimental Dynamics, 6(2) 145 - 151, 2006
  • Infuluence of force distribution on Frictional Surface to Sonic Noise Generated on Brake Discs for Motorcycle
    JSMS, 72(721) 332 - 337, 2006
  • ミクロフィブリル化セルロースを用いた光硬化複合材料の界面接着強度の改善
    上甲 圭悟; 大窪 和也; 藤井 透
    接着, 高分子刊行会, 49(11) 508 - 514, Nov. 2005
  • Development of bamboo fiber reinforced composites and their applications
    FUJII Toru; OKUBO Kazuya
    農林水産技術研究ジャーナル = Research Journal of Food and Agriculture, 農林水産技術情報協会, 28(10) 30 - 35, 01 Oct. 2005
  • Improvement of interfacial adhesion in bamboo polymer composite enhanced with micro-fibrillated cellulose
    K Okubo; T Fujii; N Yamashita
    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING, JAPAN SOC MECHANICAL ENGINEERS, 48(4) 199 - 204, Oct. 2005
  • 最近の伝動ベルトの技術動向--CVTの性能を左右する要因 (主要機械要素選定ガイド--最新技術動向がよくわかる!) -- (伝道ベルト編)
    藤井 透; 大窪 和也; 志水 政紀
    機械設計, 日刊工業新聞社, 49(6) 38 - 41, Apr. 2005
  • Effect of moisture absorption at fabrication stage on static and fatigue properties for plain-woven CF/epoxy composites
    Y Nishikawa; K Okubo; T Fujii
    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING, JAPAN SOC MECHANICAL ENGINEERS, 48(2) 73 - 78, Apr. 2005
  • ミクロフィブリル化した竹繊維を用いたグリーンコンポジットの開発
    高橋 宣也; 大窪 和也; 藤井 透
    Bamboo journal, 竹文化振興協会, (22) 81 - 92, Mar. 2005
  • 竹のセルロースミクロフィブリルを用いたナノコンポジットの創生とその特性評価 (第42回同志社大学理工学研究所研究発表会,2004年度同志社大学ハイテク・リサーチ,学術フロンティア合同シンポジウム講演予稿集)
    藤井 透; 高橋 宣也; 大窪 和也
    同志社大学理工学研究報告, 同志社大学理工学研究所, 45(4) 51 - 55, Jan. 2005
  • Method to Predict Load-Deflection Curve of Diaphragm Springs with Residual Stress for Automobile Clutches
    ABAQUUS Conference paper, 2005 121 - 130, 2005
  • Development of Green Composite using Fibrillated Bamboo Fiber
    BAMBOO JOURNAL, 22 81 - 92, 2005
  • Thermal deformation of pressure plates for manual clutches
    Hanjun He; Kazuya Okubo; Toru Fujii; Yukio Takemoto; Yasunori Doman
    SAE Technical Papers, 37(1) 113 - 118, 2005
  • Fatigue Behavior of Plain Woven CF/Epoxy Composites using Spread Tows (Effect of Tow Thicness on Crack Formation)
    NISHIKAWA Yasuhiro; MIKI Takayuki; OKUBO Kazuya; FUJII Toru; KAWABE Kazumasa
    JSMS, The Japan Society of Mechanical Engineers, 71(710) 1356 - 1361, 2005
  • Prediction of Crack Initiation for One-Piece Type Brake Disc for Motorcycles Under Overload Condition
    SAE TECHNICAL PAPER (in press), 2005
  • Most Effective Interfacial Strength for Jute Short Fiber Reinforced Polypropylene Composite and Its Fracture Model
    OKUBO Kazuya; FUJII Toru; SHIMA Kazuhiro
    Journal of the Japan Society for Composite Materials, 日本複合材料学会, 30(6) 236 - 242, 15 Nov. 2004
  • Quantitative Evaluation of Damage in Plain-Woven CF/Epoxy Composites under Cyclic Loading by Using Thermo-Elastic Technique
    Nishikawa Yasuhiro; Okubo Kazuya; Fujii Toru
    The science and engineering review of Doshisha University, Doshisha University, 45(3) 115 - 122, Oct. 2004
  • Stiffness reduction of Plain Woven CF/Epoxy Composites under cyclic loading : Influence of number of cracks and its distribution to stiffness reduction
    HIRATA Satoshi; NISHIKAWA Yasuhiro; OKUBO Kazuya; FUJII Toru
    日本複合材料学会研究発表講演会予稿集, 2004 69 - 70, 24 May 2004
  • Fabrication of Micro Composite Reinforced by Whisker of Boric Acid Aluminum
    JOUKOU Keigo; HIRAO Yusuke; OKUBO Kazuya; FUJII Toru
    日本複合材料学会研究発表講演会予稿集, 2004 103 - 104, 24 May 2004
  • 解説 最近の伝動ベルトの技術動向--新しいテンショナ方式CVT (特集 最新技術がよくわかる 2004年版 機械要素小事典) -- (伝動ベルト編)
    藤井 透; 大窪 和也
    機械設計, 日刊工業新聞社, 48(4) 58 - 61, Apr. 2004
  • ミクロフィブリル化セルロースの添加による竹繊維強化複合材料の曲げ強度、破壊じん性および衝撃強度の向上
    山下 直也; 大窪 和也; 藤井 透
    Bamboo journal, 竹文化振興協会, (21) 35 - 45, Mar. 2004
  • Study on new developed CVT having third pulley, tensioner using dry hybrid V-belts - How does it transmit power at both steady and transitional states?
    Masafumi Inowaki; Kazuya Okubo; Toru Fujii; Ryuichi Kido; Mitsuhiko Takahashi; Nobuhiro Ebi; Makoto Tanikake
    SAE Technical Papers, 0476 204 - 211, 2004
  • Study on noise generation mechanism for dry hybrid type CVT - Influence of block motions and surface roughness of pulley on sound pressure
    Junya Kanagawa; Kazuya Okubo; Toru Fujii; Ryuichi Kido; Mitsuhiko Takahashi
    SAE Technical Papers, 0477 212 - 216, 2004
  • Development of bamboo-based polymer composites and their mechanical properties
    K Okubo; T Fujii; Y Yamamoto
    COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, ELSEVIER SCI LTD, 35(3) 377 - 383, 2004
  • Development of high performance bamboo composite using micro fibrillated cellulose
    T Fujii; K Okubo; N Yamashita
    HIGH PERFORMANCE STRUCTURES AND MATERIALS II, WIT PRESS, 2(1) 421 - 431, 2004
  • 持続的再生産可能天然資源としての竹の有効利用 : 竹繊維を用いた環境適合型複合材料
    藤井 透; 大窪 和也
    成形加工, プラスチック成形加工学会, 15(9) 605 - 611, 20 Sep. 2003
  • Influence of residual stress on the load-deflection curve of diaphragm springs for automobile clutches
    Y Doman; T Fujii; K Okubo; H He
    JSAE REVIEW, ELSEVIER SCIENCE BV, 24(2) 197 - 203, Apr. 2003
  • 伝動ベルトの基礎と選定のポイント (特集 初心者にもよくわかる機械要素選定のポイント)
    藤井 透; 大窪 和也
    機械設計, 日刊工業新聞社, 47(1) 30 - 41, Jan. 2003
  • Microcrack pattern in powder solution due to desiccating shrinkage stress.
    吉川貴士; 大窪和也; 藤井透
    日本機械学会材料力学部門講演会講演論文集, The Japan Society of Mechanical Engineers, 2002 109 - 110, 11 Oct. 2002
  • サーモグラフィー法--赤外線応力画像測定によるFRPの損傷評価法 (非破壊検査特集)
    西川 康博; 大窪 和也; 藤井 透
    強化プラスチックス, 強化プラスチックス協会, 48(8) 329 - 332, Aug. 2002
  • Effect of tensile speed on Mode I fracture toughness of bonded joint using epoxy adhesive
    IMAI Katsuya; OKUBO Kazuya; FUJII Toru
    日本接着学会年次大会講演要旨集, 40 41 - 42, 22 Jul. 2002
  • 竹繊維を用いた低環境負荷型複合材料の開発とその強度特性
    紫藤 貴之; 大窪 和也; 藤井 透
    Bamboo journal, 竹文化振興協会, (19) 15 - 23, Mar. 2002
  • 223 Study on a Model of Damage Progression for Plain-Woven Carbon Fabric Composites under Cyclic Loading
    Nishikawa Yasuhiro; Okubo Kazuya; Fujii Toru; Uenoya Toshiyuki
    JSME Materials and Processing Conference (M&P), The Japan Society of Mechanical Engineers, 10(1) 493 - 496, 2002
  • 212 極低温環境下 (-196℃) で引張りおよび繰り返し荷重をうけるガラス布強化複合材料の損傷進展と機械的応答
    平尾 優介; 大窪 和也; 藤井 透; 山田 一城
    学術講演会講演論文集, 日本材料学会, 51 53 - 54, 2002
  • 大型二輪用一体型ブレーキディスクの熱変形に及ぼすブリッジ部形状の影響
    笹田 昌弘; 大窪 和也; 藤井 透
    同志社大学理工学研究報告, 同志社大学理工学研究所, 42(4) 242 - 248, Jan. 2002
  • Development of eco-composites using natural bamboo fibers and their mechanical properties.
    T Shito; K Okubo; T Fujii
    HIGH PERFORMANCE STRUCTURES AND COMPOSITES, WIT PRESS, 4(1) 175 - 182, 2002
  • Development of eco-composites using natural bamboo fibers and their mechanical properties.
    T Shito; K Okubo; T Fujii
    HIGH PERFORMANCE STRUCTURES AND COMPOSITES, WIT PRESS, 4 175 - 182, 2002
  • A study on a metal pushing V-belt type CVT - A novel approach to characterize the friction between blocks and a pulley, and shifting mechanisms
    Ryuhei Kataoka; Kazuya Okubo; Toru Fujii; Shigeru Kanehara
    SAE Technical Papers, 697 49 - 59, 2002
  • An implicit FE analysis of power transmitting mechanisms of CVT using a dry hybrid V-belt
    Kazuma Hatada; Kazuya Okubo; Toru Fujii; Ryuichi Kido; Mitsuhiko Takahashi
    SAE Technical Papers, 698 61 - 68, 2002
  • Study on crack initiation at small holes of one-piece brake discs
    Tsuyoshi Nakatsuji; Kazuya Okubo; Toru Fujii; Masahiro Sasada; Yoshihisa Noguchi
    SAE Technical Papers, 0926 61 - 68, 2002
  • Department of Mech, Engineering, Doshisha Univerysity and Mechanics of Materials Lab.
    FUJII Tohru; OHKUBO Kazuya
    Journal of the Japan Society of Polymer Processing, シグマ出版, 13(9) 624 - 626, 20 Sep. 2001
  • Fatigue Crack Propagation of Epoxy Adhesives under ModeI Loading : The governing factors of the failure mode change
    IMAI Katsuya; OKUBO Kazuya; FUJII Toru
    日本接着学会年次大会講演要旨集, 39 83 - 84, 05 Jul. 2001
  • Novel Approach to Characterization of the Strength and Toughness Degradation Due to Water Absorption for Bonded Joints Using Epoxy Adhesives
    SUZUKI Taichi; OKUBO Kazuya; FUJII Toru
    日本接着学会年次大会講演要旨集, 39 85 - 86, 05 Jul. 2001
  • Damage Development in Plain Weave Fabric GFRP at Cryogenic Temperature (-196℃)
    YAMADA Kazuki; OKUBO Kazuya; FUJII Toru
    日本複合材料学会研究発表講演会予稿集, 2001 59 - 60, Jun. 2001
  • Strenrth Properties of Carbon Fiber Composites Using Recyclable and Decomposable Poly-Lactic Acid Resin
    Jiang Jianye; Okubo Kazuya; Fujii Toru
    The science and engineering review of Doshisha University, Doshisha University, 42(1) 21 - 27, Apr. 2001
  • Crack Deflection for Adhesively Bonded Single Lap Joints
    KATO S.; OKUBO Kazuya; FUJII Toru
    Materials and Processing Conference, 2001, The Japan Society of Mechanical Engineers, 2001(9) 189 - 190, 2001
  • General Paper; Microscopic Fiber Breakage and Shear Constraint Effect in Plain Woven Glass Fabric Composites under Tension/Shear Biaxial Cyclic Loading
    Material Science Research International, Special Technical Publication-2, 250 - 255, 2001
  • 618 Adhesive Strength of Adductor Muscle in Ruditapes Philippinarum
    OGINO Hiroki; FUKUSIMA Makoto; OKUBO Kazuya; FUJII Toru
    Materials and processing conference, The Japan Society of Mechanical Engineers, 2000(8) 213 - 214, 24 Nov. 2000
  • 617 The Effect of Overlap Length on Crack Propagation of Single Lap Joints
    KATO Shunsuke; OKUBO Kazuya; FUJII Toru
    Materials and processing conference, The Japan Society of Mechanical Engineers, 2000(8) 211 - 212, 24 Nov. 2000
  • 619 Tension Shear Strength of Single Lap Joint and Residual Stress.in Adhesive Layer
    OKUBO Kazuya; FUJII Toru; YAGI Katsuhiro
    Materials and processing conference, The Japan Society of Mechanical Engineers, 2000(8) 215 - 216, 24 Nov. 2000
  • Effect of fillets on the tensile strength of adhesively bonded joints
    FUJII Toru; OKUBO Kazuya; MATSUI Takashi
    日本接着学会年次大会講演要旨集, 38 235 - 238, 22 Jun. 2000
  • 220 平織り CFRP の静的および高サイクル疲労損傷に及ぼすエポキシ母材の CNBR 変性の影響
    西川 康博; 大窪 和也; 藤井 透; 上野谷 敏之
    学術講演会講演論文集, 日本材料学会, 49 229 - 230, 2000
  • Effect of Fiber Surface Treatment on Strength Properties of Bio-degradable Composites Using Jute Fibers
    JIANG Jianye; FUJII Toru; OKUBO Kazuya; MATSUOKA Takashi
    日本複合材料学会研究発表講演会予稿集, 2000 7 - 8, 2000
  • Shifting mechanisms and variation of frictional coefficients for CVT using metal pushing V-belts
    Osamu Fujimura; Kazuya Okubo; Toru Fujii; Shigeru Kanehara
    SAE Technical Papers, 1 - 10, 2000
  • Static and Fatigue Crack Propagation of Epoxy Adhesives under Mixed Mode loading
    OKUBO Kazuya; YOSHIMITSU Hiroaki; FUJII Toru
    日本接着学会年次大会講演要旨集, 37 17 - 20, 25 Jun. 1999
  • Strength Properties of Bio-decomposable Composites Using Jute Fibers
    JIANG Jianye; OKUBO Kazuya; FUJII Toru
    複合材料シンポジウム講演要旨集, 24 141 - 142, Jan. 1999
  • Effect of Temperature on Low Cyclic Fatigue Damage Mechanism of a Plain Weave Glass Fabric Composite under Tension/Torsion Biaxial Loading
    MAEYAMA Hiroyuki; INOUE Atsushi; OKUBO Kazuya; FUJII Toru; KAWAKAMI Hiroshi
    複合材料シンポジウム講演要旨集, 24 203 - 204, Jan. 1999
  • MICROSCOPIC FATIGUE PROCESSES IN A PLAIN-WEAVE GLASS-FIBER COMPOSITE
    T FUJII; S AMIJIMA; K OKUBO
    COMPOSITES SCIENCE AND TECHNOLOGY, ELSEVIER SCI LTD, 49(4) 327 - 333, 1993
  • Improvement of Interfacial Strength of Light Curing Optical Epoxy Resin due to Micro Fibrillated Cellulose
    Adhesion, 49(11) 28 - 33
  • Fatigue Notch Sensitivity of Glass Woven Fabric Composites Having a Circular Hole under Tension/Torsion Biaxial Loading
    Journal of Composite Materials, 28(3) 234 - 251

Books etc

  • 環境調和複合材料の開発と応用
    シーエムシー出版, 2005
  • 標準材料の力学
    日刊工業新聞社, 2001

Presentations

  • CAN QUITE A FEW AMOUNT OF POLY(VINYL ALCOHOL) NANO-FIBERS SIGNIFICANTLY IMPROVE THE DURABILITY OF CARBON FIBER/EPOXY COMPOSITE
    OKUBO Kazuya
    第3回日本複合材料合同会議(JCCM-3)』, 2012
  • Reduction of squeal on laminated brake disc fastened with distributed contact pressure Engineering Mechanics Structures Engineering Geology, Gambrige
    OKUBO Kazuya
    Proceedings of Engineering Mechanics Structures Engineering Geology, 2012
  • IMPROVEMENT OF FATIGUE PROPERTY OF CARBON FIBER REINFORCED PLASTICS ENHANCED WITH NANO-SIZED SYNTHETICS POLYMER FIBERS
    OKUBO Kazuya
    International Conference Kathmandu symposia on Advanced Material, 2012
  • Experimental Study on Effect of PVA Treatment on Flexural Strength and Flexural modulus of Stampable sheet Fabricated with Bamboo Fibers
    OKUBO Kazuya
    The Seventh International Workshop on Green Composites (IWGC-7), 2012
  • 微細Polymer繊維の添加による炭素繊維強化プラスチックの疲労特性の改善
    大窪 和也
    第3回日本複合材料合同会議(JCCM-3), 2012
  • Improvement of Fatigue life of CFRP Pipe Modified with Micro Fibrillated Cellulose Subjected to Cyclic Impact loading
    OKUBO Kazuya
    Hybrid Materials 2011, 2011
  • Modeling of Stiffness Reduction of Vibration Conveyor Springs Subjected to Ultra High Cycrlic Loading under High Humidity, 8th
    OKUBO Kazuya
    International Conference on Composite Science and Technology, 2011
  • 微細ノボロイド繊維を含有したエポキシ母材を用いた平織りCFRPの疲労特性
    大窪 和也
    2011年度JCOM若手シンポジウム, 2011
  • CFRTP製板バネの初期共振周波数に及ぼす成形時の冷却速度の影響
    大窪 和也
    2011年度JCOM若手シンポジウム, 2011
  • 竹繊維とリサイクルカーボン繊維を用いたスタンパブルシートの機械的特性に及ぼすニードルパンチングの効果―グリーン材料の応用事例紹介―,
    大窪 和也
    第138回破壊力学部門委員会講演会, 2011
  • 炭化MFCの添加によるC/C複合材料の機械的特性の向上と黒鉛化による影響
    大窪 和也
    第36回複合材料シンポジウム, 2011
  • 表面をCFRPで覆ったセラミックス製防弾素材による銃弾貫通防止
    大窪 和也
    第36回複合材料シンポジウム, 2011
  • 再生炭素繊維/TPコンポジットの繊維の取り出し方法の違いによる曲げ特性の変化
    大窪 和也
    第55回日本学術会議材料工学連合講演会, 2011
  • Study on how to effectively extract bamboo fibers from raw bamboo and wastewater treatment
    OKUBO Kazuya
    56th FRP CON-EX 2011講演会, 2011
  • 微細Polymer繊維添加による炭素繊維強化プラスチックの機械的特性の改善
    大窪 和也
    56th FRP CON-EX 2011講演会, 2011
  • 竹繊維をコア材に持つサンドイッチパネルの曲げ強度の向上のためのリサイクルカーボン繊維の応用
    大窪 和也
    第48回日本航空宇宙学会関西中部支部合同秋期大会, 2011
  • 微細ノボロイド繊維の母材への添加によるCFRP板の耐久性の改善―平織りCFRP中の繊維破断の抑制とその疲労寿命の改善―
    大窪 和也
    第3回自動車用途コンポジットシンポジウム, 2011
  • CFRPと脆性材料のコアから成るサンドイッチ板の飛翔体による面外衝撃下での吸収エネルギ
    大窪 和也
    第3回自動車用途コンポジットシンポジウム, 2011
  • Improvement of Strength of Carbon/Carbon Composite by Addition of Carbonized Micro Fibrillated Cellulose Into its Precursor
    OKUBO Kazuya
    International Conference on Manufacturing of Advanced Composites, 2011
  • EFFECT OF NEEDLE PUNCHING ON STRENGTH OF STAMPABLE SANDWICH SHEET FABRICATED WITH BAMBOO FIBER AND RECYCLED CARBON FIBER MAT
    OKUBO Kazuya
    The 18th International Conference on Composite Materials, 2011
  • Improvement of mechanical properties of sandwich sheets fabricated with bamboo and recycled carbon fibers previously compound with thermoset plastic
    OKUBO Kazuya
    International Symposium on Sustainable Composites, 2011
  • Improvement of Fatigue Life of Plain-woven CFRP Enhanced with Novoloid Fibers, The Eighth Korea-Japan Joint Symposium on Composite Materials
    OKUBO Kazuya
    Proceedings of the 8th Korea-Japan Joint Symposium on composite materials, 2011
  • Modification of CFRP pipe with MFC (Micro Fibrillated Cellulose) to improve fatigue life under cyclic impact loading,The Eighth Korea-Japan Joint Symposium on Composite Materials
    OKUBO Kazuya
    Proceedings of the 8th Korea-Japan Joint Symposium on composite materials, 2011
  • 繰り返し落錘衝撃力の作用するコンベアベルトのスチールコード及びカバーゴムの破壊
    大窪 和也
    日本機械学会講演, 2010
  • 金属Vベルト式CVTの最適推力制御へ向けたベルト滑り判別手法の確立
    大窪 和也
    日本機械学会2009年度年次大会, 2010
  • 減速時の車両内の椅子からの起立抑制機構の提案
    大窪 和也
    日本機械学会2009年度年次大会, 2010
  • Calculation of Fuel Consumption on Hybrid Power System Driven by Two Motors Connected in Series with CVT
    OKUBO Kazuya
    International Multi Conference of Engineers and Computer Scientists 2010, 2010
  • 炭化MFCの炭素前駆体樹脂への添加による炭素繊維強化炭素複合材料(C/Cコンポジット)の機械的特性の改善
    大窪 和也
    日本機械学会 2010年度年次大会, 2010
  • Improvement of Strength of Bamboo Fiber Paper by Addition of MFC (Micro Fibrillated cellulose)
    OKUBO Kazuya
    The Sixth International Workshop on Green Composites (IWGC-6), 2010
  • Stiffness reduction of woven CFRP and CFRTP spring under ultra high cyclic fatigue for vibration conveyor
    OKUBO Kazuya
    The 3rd International Conference on Multi-Functional Materials and Structures (MFMS2010), 2010
  • Synthesization of CNT on Surface of C/C Composites by Alcohol CVD Method and its Effect on Coefficient of Friction between Them
    OKUBO Kazuya
    US-Japan Conferences, 2010
  • 自動二輪車用ディスクブレーキの制動時に摺動方向の垂直ひずみ分布を持つ摩擦材の鳴き特性
    大窪 和也
    自動車技術会学術講演会, 2010
  • Modification of Strain Distribution on Contact Surface of Shoe to Reduce Low frequency Squeals for Brake Disc with Small Holes
    OKUBO Kazuya
    SAE 2010 Brake Colloquium & Exhibition - 28th Annual, 2010
  • AN APPLICATION OF BAMBOO FIBER IN JAPAN EFFECT OF NEEDLE PUNCHING AND SPRING-BACK MOLDING ON STIFFNESS OF STAMPABLE BAMBOO FIBER SHEET PROCESSED WITH PRESSED MAT
    OKUBO Kazuya
    5th Vietnam Conference on Chemical Science Hanoi University of Technology, 2010
  • Application of Spring Back Molding and Needle Punching Technique to Fabrication of Stampable Bamboo Fiber Sheet processed with Pressed Mat
    OKUBO Kazuya
    The 7th Asian-Australasian Conference on Composite Materials (ACCM-7), 2010
  • Study on in-situ torque ratio estimation based on the transfer function change in rotation between two pulleys
    OKUBO Kazuya
    International Conference on Continuously Variable and Hybrid, Transmissions-CVT2010, 2010
  • Study on power transmission and loss for rubber V-belt CVT whose driving pulley has a free flange
    OKUBO Kazuya
    International Conference on Continuously Variable and Hybrid Transmissions - CVT2010, 2010
  • 超高サイクル疲労を受ける平織りCFRPおよびCFRTP製バネの多湿環境下での剛性低下と接着層中のはく離進展
    大窪 和也
    関西支部若手研究者の会, 2010
  • Calculation of Fuel Consumption on Hybrid Power System Driven by Two Motors Connected in Series with CVT
    OKUBO Kazuya
    International Multi Conference of Engineers and Computer Scientists 2010, 2010, Hong Kong
  • 繰り返し衝撃3点曲げ荷重を受けるCFRP 円筒のき裂発生と進展モード
    大窪 和也
    JCOM-38, 2009
  • 竹繊維を用いて抄紙された紙のセラック添加による比剛性の改善
    大窪 和也
    JCOM-38, 2009, 同志社今出川キャンパス
  • フィブリル化アラミド繊維により強化した圧蜜化セルロースの機械的および熱特性
    大窪 和也
    第58期日本材料学会学術講演会, 2009
  • Belt penetration and local slip in the pulley groove for metal V-belt CVT (Continuously Variable Transmission) at steady state
    OKUBO Kazuya
    Conference: IAMF 2009, 2009
  • 遠赤外線により乾燥させた圧密化竹繊維の不織布を強化材とするプレジャーボートの開発
    大窪 和也
    JCOM-37, 2009
  • 竹繊維強化ペレット製作時の繊維折損防止
    大窪 和也
    日本機械学会2008年次大会講演, 2009
  • 竹単繊維を用いて抄紙する紙の比剛性に及ぼす竹齢の影響
    大窪 和也
    日本機械学会,2009年度年次大会講演, 2009, 盛岡市,岩手大学キャンパス
  • Effect of needle punching and PVA treatment on mechanical properties of stampable sheet processed with bamboo fiber mat
    OKUBO Kazuya
    Third Japan-China Joint Seminar on Green Composites, 2009
  • 定常伝動常態下における金属ベルトタイプCVTのエレメントのすべり要因
    大窪 和也
    2008自動車技術会秋季学術講演会, 2009
  • Characterization of power transmission of V-rubber CVT having one free surface in rotation
    OKUBO Kazuya
    the15th Asia Pacific Automotive Engineering Conference, 2009
  • Effect of diameter of holes opened on frictional surface of brake disc on reduction of squeal and stick-slip at braking
    OKUBO Kazuya
    the 15th Asia Pacific Automotive Engineering Conference, 2009
  • Application of natural MFC (Micro Fibrillated cellulose) to improve fatigue life of plain CFRP
    OKUBO Kazuya
    JISSE-11(11th Japan International SAMPE Symposium & Exhibition, "Advanced Material Technology for Sustainable Development"), 2009
  • 竹繊維を用いて抄紙された工業紙へのフェノール樹脂含侵による強度改善
    大窪 和也
    JCOM-38, 2009
  • 炭素繊維強化炭素複合材料(C/Cコンポジット)の微細繊維の添加による機械的特性の改善
    大窪 和也
    日本材料学会, 第1回自動車用途コンポジットシンポジウム, 2009
  • Effect of surface treatment and addition of micro fibrillated bamboo fiber on mechanical properties of loudspeaker diaphragm
    OKUBO Kazuya
    The IUMRS International Conference in Asia, 2008, Nagoya Congress Center
  • Improvement in the mechanical properties of light curing epoxy resin with MFC (Micro-Fibrillated Cellulose)
    OKUBO Kazuya
    High Performance structure and Materials, 2008
  • Development of high strength bamboo paper using parenchyma cells
    OKUBO Kazuya
    High Performance structure and Materials, 2008
  • High Homogenization Technique for Micro-fibrillated bacteria Cellulose to Fabricate electric testing prove Disk
    OKUBO Kazuya
    Proceedings of International Workshop on Green Composites 5, 2008
  • Fatigue and impact properties of plain-woven CFRP modified with Micro Fibrillate Cellulose
    OKUBO Kazuya
    The 6th Asian-Australasian Conference on Materials, 2008
  • PPLICATION OF HIGH HOMOGENIZATION TECHNIQUE TO FABRICATION OF ELECTRIC TESTING PROVE DISK USING MICRO-FIBRILLATED BACTERIA CELLULOSE
    OKUBO Kazuya
    the Third International Conference on Material and Processing, 2008
  • APPLICATION OF HIGH HOMOGENIZATION TECHNIQUE TO FABRICATION OF ELECTRIC TESTING PROVE DISK USING MICRO-FIBRILLATED BACTERIA CELLULOSE
    OKUBO Kazuya
    the Third International Conference on Material and Processing, 2008
  • エポキシ樹脂へのMFC添加による平織りCFRPの疲労寿命の向上
    大窪 和也
    第53回FRPCON-EX 2008 講演会, 2008
  • Effect of surface treatment and addition of micro fibrillated bamboo fiber on mechanical properties of loudspeaker diaphragm
    OKUBO Kazuya
    The IUMRS International Conference in Asia, 2008
  • 遠赤外線により乾燥させた圧密化竹繊維の不織布を用いたプレジャーボー
    大窪 和也
    JCOM-37-材料・構造の複合化と機能化に関するシンポジウム-, 2008
  • Study on sit-to-stand motion for the elderly What factorscause a fall in the motion
    大窪 和也
    8th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering, 2008, Portugal
  • IMPROVEMENT OF TRANSMITTABLE TORUQUE OF CVT USING HYBRID V-BERT UNDER LUBRICATED CONDITION
    大窪 和也
    2007 ASME International Mechanical Engineering Congress and Exposition, 2008, Seattle
  • IMPROVEMENT OF TRANSMITTABLE TORUQUE OF CVT USING HYBRID V-BERT UNDER LUBRICATED CONDITION
    OKUBO Kazuya
    2007 ASME International Mechanical Engineering Congress and Exposition, 2007
  • 竹繊維を用いたFRP製小型ボートの開発
    大窪 和也
    第52回FRP.総合講演会・展示会講演要旨集, 2007
  • EFFECT of Aging of Bamboo on the Mechanical Properties of paper Fabricated with Bamboo Pulp
    大窪 和也
    THE SECOND JOINT VETNAM-JAPAN WORKSHOP ON GREEN CONPOSITE, 2007
  • STUDY ON THE EFFECT OF RESIDUAL FIBER LENGTH AND DIAMETER ON THE MECHANICAL PROPERTIES OF BFRPP
    大窪 和也
    THE SECOND JOINT VETNAM-JAPAN WORKSHOP ON GREEN CONPOSITE, 2007
  • Development of High-strength Low Thermal Expansion Bio-composites Based on MicrofibrillatedCellulose
    大窪 和也
    THE SECOND JOINT VETNAM-JAPAN WORKSHOP ON GREEN CONPOSITE, 2007
  • DEVELOPMENT OF RUBBER SHOE SOLE CONTAINING BAMBOO FIBERS FOR FROZEN ROADS
    大窪 和也
    THE SECOND JOINT VETNAM-JAPAN WORKSHOP ON GREEN CONPOSITE, 2007
  • 自動2輪車用ブレーキディスクの摺動部形状に起因するトルク変動発生メカニズム
    大窪 和也
    自動車技術会秋季学術講演会論文集, 2007, 国立京都国際会館
  • 高齢者の為の起立動作に関する研究(動作中の転倒危険性を増大させる要因)
    大窪 和也
    福祉工学シンポジウム2007講演論文集2007, 2007
  • Study on Belt Slip Behavior in metal V-Belt type CVT
    大窪 和也
    CVT・HYBRID 2007 YKOHAMA, 2007, 横浜
  • DEVELOPMENT OF A PLEASURE BOAT USING BAMBOO FIBER REINFORCED PLASTICS
    大窪 和也
    16th INTERNATIONAL CONFERENCE OF COMPOSITE MATERIALS, 2007, 国立京都国際会館
  • DEVELOPMENT OF RUBBER SHOE SOLE CONTAINNING BAMBOO FIBERS FOR FROZEN ROADS
    大窪 和也
    16th INTERNATIONAL CONFERENCE OF COMPOSITE MATERIALS, 2007, 国立京都国際会館

Works

  • 平成14年度地域新生コンソーシアム研究開発事業(開繊技術を応用した薄層ボイドレスMAPシートの開発)
    2002 -2003

Industrial Property Rights

  • Patent right
    炭素繊維の回収方法
    特願2012-069382
  • Patent right
    ブレーキディスク
    特願2011-033779
  • Patent right
    繊維強化プラスチック用組成物及び炭素繊維強化プラスチック
    特願2012-046521
  • Patent right
    不織布、及び、この不織布の製造方法
    特願2012-039703
  • Patent right
    再生炭素繊維の製造方法
    特願2012-007831
  • Patent right
    コンベアベルトの縦裂き検出用ループコイルの耐久性評価装置および方法
    特願2011-106384
  • Patent right
    コンベヤベルトの縦裂き検出用ループコイルおよびその製造方法
    特願2011-106379
  • Patent right
    コンベアベルトの衝撃試験装置および方法
    特願2011-055190
  • Patent right
    不織布,この不織布の製造方法及びこの不織布を用いたサンドイッチ材
    特願2011-057560
  • Patent right
    炭素繊維強化炭素複合材料及びその製造法
    特願2010-188976
  • Patent right
    急傾斜コンベヤベルトのフランジの屈曲耐久性評価装置および評価方法
    特願2010-130236
  • Patent right
    コンベヤベルトの耐衝撃性の評価システムおよび評価方法
    特願2010-130224
  • Patent right
    MFCをC/C複合材料用プリフォーム材への添加による高強度C/C素材
    特願2009-194259
  • Patent right
    繊維強化複合体
    特願2010-012030
  • Patent right
    コードの張力制御装置
    特許公開平6-255883
  • Patent right
    ベルト歯数測定装置
    特許公開平6-337972
  • Patent right
    カーブコンベア
    特許公開平7-223716
  • Patent right
    ベルト保持装置
    特許公開平7-323907
  • Patent right
    ベルト保持装置
    特許公開平7-323908
  • Patent right
    コンベア・ベルトの製造方法
    特許公開平8-80581
  • Patent right
    コンベア・ベルト
    特許公開平8-81027
  • Patent right
    カーブコンベア
    特許公開平8-133438
  • Patent right
    カーブコンベアベルトの製造方法
    特許公開平8-244932
  • Patent right
    カーブコンベアベルト及びカーブコンベア
    特許公開平8-319013
  • Patent right
    カーブコンベア
    特許公開平8-319014
  • Patent right
    カーブコンベアベルトの製造方法
    特許公開平9-58832
  • Patent right
    摩擦力の測定装置
    特許公開平9-243482
  • Patent right
    橋梁用伸縮継手
    特許公開平11-264107
  • Patent right
    平ベルト
    特許公開2000-351429
  • Patent right
    被着体の剥離方法
    特許公開2004-35792
  • Patent right
    ディスクブレーキ装置及びディスクブレーキ装置の制動方法
    特許公開2004-347095
  • Patent right
    人工筋肉
    特許公開2005-58351
  • Patent right
    感温性粘着テープの剥離方法
    特許公開2005-26018
  • Patent right
    樹脂組成物の製造方法
    特許公開2005-161850
  • Patent right
    光硬化樹脂複合材料とその製造法
    特願2005-314645
  • Patent right
    繊維強化複合材料およびその製造方法
    特願2008-191034
  • Patent right
    炭素繊維強化炭素複合材料及びその製造法
    特願2009-194259

Research Projects

  • Investigation and improvement of interfacial strength between fiber and matrix under impact loading
    小武内 清貴; 大窪 和也
    本年度は,引張型SHPB装置および計装式振子型衝撃試験機を用い,異なるひずみ速度下における強化繊維-母材樹脂間の界面せん断強度および一方向複合材料の衝撃吸収エネルギの評価方法を確立した.確立した評価方法を用い,炭素繊維/エポキシ系およびガラス繊維/エポキシ系の界面せん断強度を調査したところ,ガラス繊維/エポキシ系においては,ひずみ速度の増加に伴って,両者の界面せん断強度は増加したが,炭素繊維/エポキシ系においては,両者の界面せん断強度は,ひずみ速度の増加に伴って低下した.これは一方向複合材料の衝撃エネルギにおいても同様となった.また,母材エポキシ樹脂をサブミクロンガラス繊維によって改質した場合,炭素繊維/エポキシ系において,高ひずみ速度条件下での界面せん断強度,ならびに一方向複合材料の衝撃吸収エネルギが増加した. これは,母材に添加した高ひずみ速度下において,サブミクロンガラス繊維と母材との間に剥離が生じ,母材中の弾性波の進展を阻害したためと考えられる.現在は,より詳細にサブミクロンガラス繊維添加の効果を調査中である. また,炭素繊維において,その表面改質(サイジング処理)が,炭素繊維/エポキシ樹脂間の界面せん断強度におよぼす影響を,異なるひずみ速度下で調査したところ,現在一般に使用されているサイジング処理による界面せん断強度向上効果は,ひずみ速度の増加に伴って減衰することを見出した.この繊維表面処理の効果については,より詳細な調査を,来年度に向けて実施予定である., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2021/04 -2024/03, Grant-in-Aid for Scientific Research (C), Doshisha University
  • Formulation of design criteria and improvement of durability of carbon fiber reinforced composite joint subjected to in-plane and out of plane loading.
    大窪 和也; 小武内 清貴
    申請時の研究計画調書に従い,CFRTP(炭素繊維強化熱可塑プラスチックス)を用いた際の広範囲な種別の接合構造を想定し,その全般を含むような接合構造の強度設計手法と設計規準を社会に提唱すると共に,長期使用に対する疲労耐久性を高めるための新技術を社会に提供し当該学術・産業分野に貢献する事を目的として研究を行った. 特に当該年度においては,昨年度までの研究結果を発展させ,微細繊維を内部に含有させた締結用の弾性カラー(以下,締結カラーと記載)の併用効果や,締結部のボルト孔付近での再溶融の効果,および締結後の再度の応力分配の考え方を利用して,その接合部分の強度と疲労耐久性を向上させるための技術開発を行った.また添加する微細ガラス繊維の添加率を変更した場合の改善効果の増減を調査すると共に,特に疲労寿命の改善効果を左右する内部の損傷進展機構の解明に注力した. その結果,本件のボルト締結接手の疲労信頼性は,CFRTPの強化繊維自体の破断や,継手部付近にあるCFRTP表面の摩擦力による摩滅等ではなく,ボルト締結用の円孔部の周縁部にある強化繊維の局所的な座屈の発生の有無に支配される事を明らかにした.具体的には,締結カラーを併用しない場合には,初期の締結トルクを適切に与えた場合でも,特に繰り返し疲労荷重下ではその締結力が低下し,ボルトのネジ山の先端からの長手方向の圧縮力を受ける円孔縁面付近で強化繊維の局所的な座屈が生じ,それが起点となって継手の信頼性を著しく低下させるが,締結カラーを併用するとこの局所座屈の発生が抑制されると共に,さらにその締結カラーに微細繊維を添加した場合には,一旦,微細な局所座屈が発生してもそれを起点とする開口き裂の変位を適切に力学架橋し,損傷の増大化を遅延できる事がわかった,この効果により,継手としての疲労耐久寿命を向上できる事がわかった., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2019/04 -2023/03, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Improvement in mechanical properties and fatigue life of CFRTP due to an addition of sub-micron glass fibers and their mechanisms
    Fujii Toru
    First, the effect of submicron glass fiber (sGF) addition to the VE matrix of C-SMC having various chopped carbon fibers was investigated. However, except for the impact strength, stable performance improvement of mechanical characteristics including fatigue life was not obtained due to sGF addition. High molecular weight thermos-plastic epoxy (TP-EP) having almost the same basic molecular structure as the thermosetting epoxy (TS-EP), CFRTP whose mechanical performance is comparable to TS-EP CFRP was obtained. The key to the performance of this material is the adhesive strength in CF/EP interface. We have developed a FRTP unidirectional tape with 3% sGF added to PP and a laminated board using this tape. In CFPP, the addition of sGF significantly improves impact resistance. The hemispherical molded product can bring out its maximum characteristics. CFTP using TP-EP significantly improved the CAI strength. This is due to an introduction of many fracture origins by sGF., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2018/04 -2021/03, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Design Criterion and Improvement of Durability of Carbon Fiber Reinforced Composites Fastened by Bolt
    OKUBO Kazuya; Kumamoto Souichiro; Nishida Hironori; Carvelli Valter; Ootani Ryouhei; Yamada Yuto; Tanaka Aya; NAGAI Keisuke; Shioya Wataru; Imagawa Soichiro; Hayashi Kenta
    The purpose of study is to develop novel technique to modify the designing aspect for mechanical joint of CFRP (Carbon Fiber Reinforced Plastic) and metal plate fastened with conventional bolt, and also to propose a design criterion of the joint considering the durability under cyclic fatigue loading. According to the plan, at first, changes of mechanical properties of the conventional joint and its points to be considered was clearly shown to start the study. Then, effects of novel techniques were experimentally shown, where micro-sized glass fibers were previously added into the matrix of jointed CFRP and the modified collar surrounding the bolt. The design criterion was proposed to explain the change of strength of the joint considering the theory of energy release rate with damage propagation around the bolt hole. At last, an original novel technique where the byte plate and modified resin film was applied around the bolt hole was developed to improve the fatigue durability., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2015/04 -2019/03, Grant-in-Aid for Scientific Research (C), Doshisha University
  • Mechanisms of fatigue life extension of CFRP due to nano fibers and development of prepreg using nano fiber modification
    Fujii, Toru
    The fatigue life of CFRP is well improved by modifying the polymer matrix with nano fibers such as Cellulose Nano Fibers due to an increase of observed adhesive strength between carbon fiber (CF) and polymer matrix. When nano fibers (NF) are well dispersed in the matrix, the physical modification of matrix becomes significant while they stick on CF, their effect disappears. NF must be enough longer to slide across two adjacent fibers. If nano fibers stick on the CF surface, the physical modification effect does not happen. Plastic deformation due to nano/micro crazing is induced at NF ends. Stress concentration at the CF/matrix interface becomes low. Then, fatigue life is extended. UD prepreg was successfully developed using loosed fiber tows. CF-SMC using vinylester was also developed using sub-micron glass fibers whose mechanical properties are greater than those of commercially available CF-SMC. The applicability of nano fibers was also demonstrated using PP matrix for CFRTP., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2014/04 -2017/03, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Fatigue life improvement of CFRP due to hybrid modification of polymer matrix with cellulose nano fibers and nano rubber particles
    FUJII Toru; OKUBO Kazuya
    Epoxy matrix of CFRP was physically modified with different types of cellulose nano fibers (CNF) including bacterial cellulose, whose weight content was about 0.3-0.8wt%. Any types of CNF incredibly extend the fatigue life of CFRP in comparison with the unmodified one. An excessive amount of CNF decreases the life extension effect. When CNF were simultaneously mixed with nano rubber particles, the tensile strength of modified CFRP appreciably increased without scarifying other properties due to a hybrid effect. More fatigue life extension is expected due to an appropriate hybrid modification. 50nm (in diameter) PVA, 500nm glass and 700nm PET fibers were also tested instead of CNF. Those fibers extended the fatigue life of CFRP as well in spite of difference in their mechanical performance. Thin (smaller than 1 μm) fibers are useful as a matrix modifier of CFRP. When an appropriate content of CNF was mixed into epoxy matrix, less fiber debonding occurred. Other resin matrices such as vinylester can be modified with CNF for fatigue life extension., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2011 -2013, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Development of Eco-friendly polymer composite with low coefficient of expansion ratio using micro fibrillated cellulose
    OKUBO Kazuya
    We developed novel technique to apply very thin additional fibers such as micro-fibrillated cellulose(MFC) to improve the mechanical fatigue properties with low thermal expansion of conventional composites based upon polymer as matrix and long fibers as main reinforcement, respectively. In fabrication, agglomeration of micro-fibrillated cellulose which was utilized as the "third material" in the liquid resin was adequately prevented by a dispersion technique with shear in very thin layer. The results showed that mechanical properties were improved by that hierarchy of reinforcement was created around the interphase due to the relative difference in scale between micro-sized fibers and reinforcing main fibers., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2008 -2011, Grant-in-Aid for Scientific Research (C), Doshisha University
  • Study on how to extract nano fiber clusters from bamboo and their application
    FUJII Toru; OKUBO Kazuya
    Nano fibers called MFC (Micro-Fibrillated Cellulose) were extracted from raw bamboo as well as other plant pulps. When they are mechanically extracted, MFC forms NFC (Nano Fiber Cluster). First, PLA was reinforced with fibrillated bamboo mono-filaments/BNFC. PLA is brittle and less temperature resistance. With an increase of mechanical process for extracting, NFC becomes complicated. The degree of cluster, α was well quantitatively determined by water absorption since the surface of nano fiber cellulose being hydrophilic increased with an increase of fibrillating process. When BNFC was mixed with PLA to form compounds for improving its toughness, strength and thermal resistance, α=3.5 was suitable. Light curing epoxy was well modified in its ductility by adding a small amount of NFC. NFC was hydrophilic, and solvent replacement method such as ethanol was developed. The fracture toughness of light curing epoxy significantly increased due to a small amount of NFC, 0.5~1% dispersion. Finally, epoxy matrix of carbon fiber composites was modified with NFC up to 1% and their high cycle fatigue strength was examined under tension-tension loading. The significant extension of fatigue life was obtained when 0.3wt% NFC was mixed into epoxy resin, where the ethanol replacement method was also applied., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2008 -2010, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Development of green composites using thermoplastics and bamboo fiber
    FUJII Toru; OKUBO Kazuya; TANAKA Tatusya
    Bamboo fibers were extracted from raw bamboo such as Moso (Chinese) and Madake (a typical Japanese bamboo) by following three methods. (1) Mechanical processing by using the conventional fiber loosening machine. It has a rotating nail drum where thin bamboo strips are used. Younger bamboo than one year old is suitable for this method. (2) Alkali (NaOH) treatment: First, bamboo strips are immersed in a hot alkali bath for a couple hours, then, they are machined(3) Steam explosion method: Raw bamboo is set in a steam chamber which will be filled with super heated steam at high pressure. Then, the steam is abruptly released. Micro-cell explosion occurs in cells. Then, fibers are extracted by using the loosing machine from steam exploded bamboo. Relatively long fibers are obtained by the alkali treatment and the steam explosion method while short fibers are extracted when bamboo is mechanically processed. However, long fibers can be obtained enough to be used for fabricating non-woven fabrics by mixing thermoplastic (TP) fibers as long as the bamboo is very young. Non-woven fabrics using relatively short bamboo fibers as well as TP fibers such as PP and PE were successfully developed. It can be used as a green composite material to form inner components of automobiles such as ceiling and rear trays. PIA (Poly Lactic Acid) fibers made from corns can also be used instead of PP fibers. Fibers shorter than 50 mm are mixed with TP using a twin screw extruder to fabricate green composites pellets. In order to increase the tensile/bending strengths of the injection molded parts, the bamboo fiber diameter is a key as well as the aspect ratio. Thinner than 0.1 mm is desirable for the nominal diameter of bamboo fibers as well as a high aspect ratio greater than 20. Through the twin extruder path, the aspect ratio of bamboo fibers in a composite decreases. The maximum tensile strength of a bamboo fiber (50%wt content) /PP composite is about 50 Mpa. The maleic acid modification is obliged to increase the mechanical properties of bamboo fiber green composites. The mechanical properties of random bamboo fiber mats/Polyester composites (BFRP) were measured. The BFRP was fabricated by RTM (Resin Transfer Molding) while long bamboo fibers were extracted from MOSO bamboo by the alkali treatment. The bamboo mats were fabricated by using a carding machine in conjunction with a needle punching machine. The mats was very thick and the resultant BFRP had a low strength not enough to use for fabricating small boats (5 m long). Then, in order to increase the bamboo fiber fraction, bamboo mats were compressed in advance and used. The observed strength of the improved BFRP is strong enough to use for the boats. However, the study on water absorption tells us to pay a lot of attention on water. An appropriate treatment to prevent the water absorption during service is strongly suggested. The present study shows that not only the mechanical properties of PIA but also the heat resistance at elevated temperature are well improved due to inclusion of micro-fibrillated bamboo fibers. Short bamboo fibers can enhance the tensile strength and heat resistance, but the impact strength becomes low due to bamboo fibers. On the other hand, if the bamboo fibers are slightly fibrillated, the impact strength is well improved. Finally, the mechanical and thermal properties of the composite materials based on PLA are sometimes higher than those of 20 wt% glass fiber/ABS composite. The fibrillated bamboo fibers are also applied to fabricate the proving disks for semi-conductors., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2005 -2007, Grant-in-Aid for Scientific Research (B), Doshisha University
  • Effect of a little water absorption on the long-term durability of advanced composites and how to improve the life
    FUJII Toru; OKUBO Kazuya
    Even under the normal condition where the relative humidity is 60% or lower, a little water in the atmosphere penetrates into advanced composites such as CFRP and accelerates the fatigue degradation under cyclic loading. The present study revealed that we must pay a lot of attention to long-term degradation due to a little water absorption. The mechanism on the relationship between a little water and degradation at the fiber/matrix interface is a key for the long-term durability for advanced fiber composites. The effect of protection from water penetration during fabrication process on the static and fatigue properties was studied for plain woven CFRP. The static strength and fatigue life were examined when the humidity condition changed at each stage; mixing, lamination, storage and testing stage. The experimental results showed that the static strength and fatigue life of plain woven CFRP were significantly improved even when the material was protected from water penetration during the lamination stage. The protection from water penetration during the lamination stage improved the resistance of crack growth and interfacial shearing strength at the interface between fiber and matrix. Such improvement of fiber/matrix interfacial properties contributed to the improvement the static strength and fatigue life of plain woven CFRP improve. How to observe and characterize the fatigue degradation of advanced composites under cyclic loading was also focused using the thermo-elastic image techniques for composites. The experimental results showed the damage initiation points were widely scattered in the materials due to its woven structure. In order to obtain accurate damage information, thermo-elastic damage analysis (TDA) was developed and used. The present study well demonstrated that the progressive fatigue degradation was well characterized by analyzing the thermo-views taken simultaneously during fatigue. The fatigue life of woven fabric composites was significantly extended by using spread tows as well. The flat tows reduce the crack initiation occurring in the transverse yarns., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 2003 -2004, Grant-in-Aid for Scientific Research (C), DOSHISHA UNIVERSITY
  • Study on the fatigue crack and secondary crack growth in the adhesive layer under Modes I, II and Mixed mode loadings
    FUJII Toru; OKUBO Kazuya
    Bumpy surface is formed on the fractured surface of adhesively bonded DCB joints under mixed mode loading in conjunction with a crack cohesively propagates. The mechanism for formation of such bumpy fractured surface can be explained based on the stress analysis at the crack tip in conjunction with the criterion for an occurrence of crazes. The crack propagation resistance increases under cyclic mixed mode loading with an increase of mode II component. An increase in threshold is appreciable. The crack for epoxy adhesive under mode I loading propagates from cohesively to interfacailly as the energy release rate range, ?G_I decreases. Mixed mode failure appears between to cohesive and interfacial failure modes. The crack once is arrested at a certain ?G_I. Its magnitude depends on the surface condition (surface treatment) as well as other conditions such as cyclic load frequency. The crack resumes to propagate after a while under the normal laboratory condition, which is named as "Secondary crack growth". No secondary crack growth occurs when the fatigue tests are conducted under extremely dry condition. The characteristics of fatigue crack growth are strongly influenced by loading mode, such as Mode I, Mode II or mixed mode. The secondary crack growth occurs even at 65 % relative humidity at room temperature. Small amount of water absorption also affects the failure of carbon fiber epoxy composites appreciably. When the composite is fabricated under the laboratory condition, the tensile strength decreases 20 % lower than that of the sample fabricated with less moisture. At high cyclic fatigue, a small amount of moisture in air also strongly affects the fatigue failure of the composite. Little epoxy resin can be identified on the broken fibers. For single lap joints subjected to a tensile shear load, cracks occur at the bond termini where the stress singularity exists. With increasing the applied load, the crack interfacailly grow inward, then, they change their direction into the adhesive layer. It happens during the stable crack propagation period. The total energy release rate criterion can be used to estimate where and when such crack deflection occurs. The effect of residual stress due to adhesive shrinkage during consolidation could be one of major reasons why single lap joins become strong when the adhesive layer becomes thin., Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, 1999 -2001, Grant-in-Aid for Scientific Research (C), Doshisha University
  • ニッタケーシング株式会社
    ニッタケーシング株式会社, 奨学寄付金, 奨学寄附金, Competitive research funding
  • 株式会社本田技術研究所
    株式会社本田技術研究所, 奨学寄付金, 奨学寄附金, Competitive research funding
  • 横浜ゴム株式会社
    横浜ゴム株式会社, 奨学寄付金, 奨学寄附金, Competitive research funding
  • ニッタ株式会社
    ニッタ株式会社, 奨学寄付金, 奨学寄附金, Competitive research funding
  • Fracture and Damage of Composite and Adhesives,Bolt Transmission
    Competitive research funding
  • 複合材料及び接着剤の破壊ならびに損傷,ベルト伝動システム
    Competitive research funding

Social Contribution

  • 文部科学省「サイエンス・パートナーシップ・プログラム」, 2004
  • 財団法人日本科学技術振興団ウインター・サイエンスキャンプ, 2003
  • ふれあいサイエンス, 2000
  • ふれあいサイエンス, 1999

Teaching Experience

  • 英書講読
    同志社大学
  • 機械工学概論
    同志社大学
  • コンピュータプログラミング
    同志社大学
  • 機械設計法
    同志社大学
  • 機械物理実験
    同志社大学
  • 構造設計特論
    同志社大学
  • 破壊力学
    同志社大学
  • 弾性力学
    同志社大学
  • 材料力学
    同志社大学

Research Seeds

  • Novel approach on power transmitting theory of frictional belt
    Research Fields: Machinery and Measuring Equipment
    Affiliation/Name: Kazuya Okubo

    Patent Information: 特願 2012-136182(外国出願有:PCT), 特願 2010-130224