Volume 61 (2016)
No.1 Special Issue on Tribology Roadmap in Commemoration of the 60th Anniversary of JAST
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Foreword | In Commemoration of the 60th Anniversary of JAST | Takahisa KATO | 1 | 1 | |
| Commemoration of the 60th Anniversary of JAST | Essay | The Evolution of Tribology | Koji KATO | 1 | 2 |
| To God from Devil | Motohiro KANETA | 1 | 3 | ||
| Forty Years after Enrolling in JSLE and Recent 10 Years of JAST | Yoshio KUMADA | 1 | 4 | ||
| Foreseeability | Makoto NISHIMURA | 1 | 5 | ||
| Tribology is the Stage of Technologies | Hisashi MACHIDA | 1 | 6 | ||
| Collaboration between Industry and University | Takashi YAMAMOTO | 1 | 7 | ||
| Special Issue on Tribology Roadmap in Commemoration of the 60th Anniversary of JAST | Prologue to the Special Issue on “Tribology Roadmap in Commemoration of the 60th Anniversary of JAST” | Tsunamitsu NAKAHARA | 1 | 8 | |
| Explanation | Purpose of Tribology Roadmap and Summary of the Committee Report | Tsunamitsu NAKAHARA and Yasuhisa ANDO | 1 | 9 | |
| Overlooking Map of Tribotechnology —Classification of Tribology Industries and Tribological Issues— | Takahisa KATO | 1 | 16 | ||
| Roadmaps on Tribo-Components Derived from Systems and Subsystems of Spacecraft | Shingo OBARA | 1 | 19 | ||
| Roadmaps of Rolling Bearings | Shoji NOGUCHI | 1 | 27 | ||
| Trends of Lubricants | Masabumi MASUKO | 1 | 35 | ||
| Commemoration of the 60th Anniversary of JAST | Record | Memories of Japanese Society of Tribologists in the Last 10 Years —The 10 Years from the 50th Anniversary— | 60th JAST Editorial Committee | 1 | 39 |
| Original Contribution | Dry Friction Properties of Nanostripe Structures Consisting of Hard and Soft Metals | Shunsuke ABE and Yasuhisa ANDO | 1 | 50 |
No.2 Special Issue on Automotive Resource Saving and Energy Saving in Commemoration of the 60th Anniversary of JAST
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Occasional Thoughts as a Tribologist | Kenichi KOMIYA | 2 | 63 |
| Special Issue on Automotive Resource Saving and Energy Saving in Commemoration of the 60th Anniversary of JAST | Prologue to the Special Issue on “Automotive Resource Saving and Energy Saving in Commemoration of the 60th Anniversary of JAST” | Takashi NAKAMURA | 2 | 64 | |
| Explanation | Improvement of Fuel Efficiency of Passenger Cars by Taking Advantage of Tribology | Takashi NAKAMURA | 2 | 65 | |
| Research Trend of Friction Loss Reduction in Internal Combustion Engines | Yuji MIHARA | 2 | 71 | ||
| Reduction of Piston Ring Friction | Hidetsugu YAMAMOTO | 2 | 78 | ||
| Technical Trend about Friction Reduction of Engine Valve Train System | Yutaka MABUCHI | 2 | 84 | ||
| Technical Trend about Friction Reduction of Engine Bearings | Shu KAMIYA and Toru DESAKI | 2 | 92 | ||
| Loss Reduction of Rolling Bearings for Automobile | Takashi SADA | 2 | 98 | ||
| Technology for Reduction in Tire Rolling Resistance | Keizo AKUTAGAWA | 2 | 104 | ||
| Forecasting of Automotive Resource Saving and Energy Saving | Atsushi SUZUKI | 2 | 109 | ||
| Lecture of Tribology | Lecture | Test Machine and Method to Evaluate Surface Durability | Masahiro FUJII | 2 | 116 |
| Original Contribution | Study on the Dynamic Performance Measurement of a Ball Bearing Used in the Car Auto-Tensioner | Akiyoshi NAKASE, Takahiro MIZUNO and Liming LOU | 2 | 120 | |
| Growth of Cavitation in Journal Bearing and Effect of Cavitation on Behavior of Bearing | Takefumi OTSU and Kazuki NISHIDA | 2 | 127 |
No.3 Special Issue on Advanced Technologies and Prospects of Solid Lubrication
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Plain Bearings and Tribology | Yoshiaki SATO | 3 | 141 |
| Special Issue on Advanced Technologies and Prospects of Solid Lubrication | Prologue to the Special Issue on “Advanced Technologies and Prospects of Solid Lubrication” | Hiroshi SHIOMI | 3 | 142 | |
| Explanation | Future and Issues of Solid Lubrication | Noritsugu UMEHARA | 3 | 143 | |
| Key Points for Handling of Bonded Solid Film Lubricants —Molybdenum Disulfide Type Coatings— | Masahiro KAWAMURA | 3 | 149 | ||
| Addition of Solid Lubricants to Oil and Grease | Satoshi KASHIWAYA | 3 | 155 | ||
| Development of Sliding Materials Considering Tribochemical Reactions | Takashi MURAKAMI | 3 | 161 | ||
| Pantograph Contact Strip for Shinkansen and Its Lubrication Technology | Yoshitaka KUBOTA | 3 | 167 | ||
| Technologies of Solid Lubrication in Electrodynamic Tether for Conservation of Space Environment | Koji MATSUMOTO and Satomi KAWAMOTO | 3 | 173 | ||
| Explanation | Key Points to Be Considered in Plastic Gear Design | Ichiro MORIWAKI | 3 | 180 | |
| Tribo-Tool Develpment for the Breakthrough | Technical Information | Test Machine for Fretting in Hydrogen Environment | Masanobu KUBOTA and Ryosuke KOMODA | 3 | 187 |
No.4 Special Issue on Tribology Learned from Biological Systems
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Winners of 2015 Distinguished Tribologists Award Winners of 2015 Best Paper Award Winners of 2015 Best Paper Award of Tribology Online Winners of 2015 Tribo-Technology Award Winners of 2015 Award for Young Tribologists Winners of 2015 Award for Student Tribologists |
4 | 197 | |||
| The 6th Tribology Heritage | No.16 Soda Library | 4 | 213 | ||
| Special Issue on Tribology Learned from Biological Systems | Prologue to the Special Issue on “Tribology Learned from Biological Systems” | Ken SAWADA | 4 | 214 | |
| Explanation | Biological Surface Friction —Biomimetic Approach Based on Self-Organization— | Masatsugu SHIMOMURA, Yuji HIRAI, Naoto OKUDA, Ryuichiro MACHIDA, Syûhei NOMURA, Masahiro ÔHARA and Miki HASEYAMA | 4 | 215 | |
| Friction Phenomena on Fingertip Surfaces | Yoshimune NONOMURA | 4 | 222 | ||
| Tribology of Articular Cartilage | Hiromichi FUJIE | 4 | 228 | ||
| Tribology in Scales of Sandfish | Hiroshi KINOSHITA | 4 | 235 | ||
| Tribology Inspired by Gecko Feet | Tetsuo YAMAGUCHI, Akira AKAMINE and Yoshinori SAWAE | 4 | 243 | ||
| Friction Drag Reduction Inspired by Dolphins' Skin | Yoshimichi HAGIWARA | 4 | 249 | ||
| The Tribo-Soshi, Essays from Tribologists | Essay | Story of a Man Possessed with Acoustic Emission | Takeo YOSHIOKA | 4 | 256 |
| Essay for Overseas Experiences in Tribology —Around the World— | Up-to date News | Experiences at Imperial College London | Koji HOSHINO | 4 | 261 |
| Original Contribution | Improvement of Rolling Bearing Life by Bonding of Non-Metallic Inclusions with Matrix (Part 1) —Relationship between Isostatic Pressing Conditions and Life Improvement— | Takashi SADA, Yuuki NONAKA, Tsuyoshi MIKAMI and Katsuhiko KIZAWA | 4 | 264 | |
| X-Ray CT Imaging of Grease Behavior in Ball Bearing and Numerical Validation of Multi-Phase Flows Simulation | Takashi NODA, Kenichi SHIBASAKI, Shinji MIYATA and Masato TANIGUCHI | 4 | 275 |
No.5 Special Issue on Tribology in Construction Machinery Technology
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Sometimes the Heart Sees What is Invisible to the Eye | Hiroshi TANI | 5 | 293 |
| Special Issue on Tribology in Construction Machinery Technology | Prologue to the Special Issue on “Tribology in Construction Machinery Technology” | Makoto KANDA | 5 | 294 | |
| Explanation | Recent Trends in Cylinder Rod Seals for Hydraulic Excavators | Norikazu TAMENAGA | 5 | 295 | |
| Transition of Technology and Tribology in Shield Machines | Takashi NAKANO | 5 | 301 | ||
| Tail Seal Grease for Shield Machines | Takashi ARAI | 5 | 308 | ||
| Environmentally Friendly Technology and Tribology for Rough Terrain Cranes | Naoto KAWABUCHI | 5 | 314 | ||
| Sophistication of Drilling Machine —Efforts Aiming toward Common Use of Renewable Energy Heat— | Haruhiko ITO | 5 | 321 | ||
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | Experience Story at Czech-Japan Tribology Workshop | Toshifumi MAWATARI | 5 | 330 |
| Original Contribution | Tribology Characteristics of HFO and HC Refrigerants with Immiscible Oils —Effect of Refrigerant with Unsaturated Bond— | Tatsuya SASAKI, Kota MIZUNO, Hideto NAKAO, Hideaki MAEYAMA and Shinichi TAKAHASHI | 5 | 334 |
No.6 Special Issue on Tribology Associated with Electricity
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Practical Technology and Tribology | Eiji NAGATOMI | 6 | 345 |
| Special Issue on Tribology Associated with Electricity | Prologue to the Special Issue on “Tribology Associated with Electricity” | Yosuke TSUKIYAMA | 6 | 346 | |
| Explanation | Electrically Conductive Coatings Utilizing Diamond-Like Carbon | Takanori TAKENO | 6 | 347 | |
| Recent Trends in Electrically Conductive Greases | Hiroki YODA and Hisaya NAKAMURA | 6 | 355 | ||
| Tribology in Current Collecting Materials of Electric Railway | Chikara YAMASHITA | 6 | 361 | ||
| Technology in Contact Roller Charging Device of Electrophotographic Printer | Takayuki WAKAI | 6 | 368 | ||
| Novel Developments of Electrostatic Separation Technology | Masato SAEKI | 6 | 376 | ||
| Lecture of Tribology | Lecture | The Foundation of Nanoindentation | Toshiro OKAWA | 6 | 382 |
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | A Week Trip to North America | Seiya WATANABE | 6 | 389 |
| Original Contribution | Observation of Residual Stress Variation on Rolling Fatigue of Steel Ball | Ryousuke ANO, Masahiro FUJII and Hiroshi OHSAKI | 6 | 393 |
No.7 Special Issue on Vibration Phenomenon on Tribology
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Foreword | The Valediction by the Ex-President | Takahisa KATO | 7 | 413 | |
| The Inaugural Address by the President | Shirou NAKANO | 7 | 414 | ||
| Special Issue on Vibration Phenomenon on Tribology | Prologue to the Special Issue on “Vibration Phenomenon on Tribology” | Masaaki YAMANE | 7 | 415 | |
| Explanation | Countermeasures against Vibrations in Sliding Friction | Ken NAKANO, Chiharu TADOKORO, Satoru MAEGAWA and Naohiro KADO | 7 | 416 | |
| Case Studies of Vibration Problem and Countermeasure in Rotating Machinery —Vibrations Caused by Bearing— | Masao KOBAYASHI | 7 | 423 | ||
| Diagnosis Method and Vibration of Rotating Machinery with Damaged Bearings | Ho JINYAMA | 7 | 431 | ||
| Noise and Vibration of Tires —Effect of Road Roughness— | Nobutaka TSUJIUCHI and Masami MATSUBARA | 7 | 437 | ||
| Brake Noise Induced by Friction | Masaaki NISHIWAKI | 7 | 443 | ||
| Vibration and Noise in Geared System | Hiroshi IIDA | 7 | 451 | ||
| Chatter Vibration in Cutting | Norikazu SUZUKI | 7 | 457 | ||
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | The Report on Ecotrib2015 and Visiting ETH | Yuriko KONDO | 7 | 463 |
| Original Contribution | Observation of Formation Process of Ridge Mark Arising from Electrical Pitting by Using Thrust Bearing | Shoji NOGUCHI | 7 | 467 |
No.8 Special Issue on Phenomenological Tribology
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | ʻTribologyʼ and I | Shuzo SANDA | 8 | 493 |
| Special Issue on Phenomenological Tribology | Prologue to the Special Issue on “Phenomenological Tribology” | Ryo TSUBOI | 8 | 494 | |
| Explanation | Hierarchy of Law of Friction —Departure from the Phenomenology— | Hiroshi MATSUKAWA | 8 | 495 | |
| Mechanism and Control of Nanoscale Superlubricity and Adhesion | Naruo SASAKI and Kouji MIURA | 8 | 506 | ||
| Fluid Film Lubrication at Nanometer Gaps | Kenji FUKUZAWA | 8 | 513 | ||
| Real Time TEM Observation of Stick-Slip Motions on Ag Surface | Takaaki SATO and Hiroyuki FUJITA | 8 | 519 | ||
| Microscopic Structure of Water Molecules Adsorbed on Metal Surfaces | Hiroshi OKUYAMA | 8 | 525 | ||
| Photon Emission Induced by Fracture of Hard Brittle Materials —Fractoluminescence— | Tadashi SHIOTA and Kouichi YASUDA | 8 | 531 | ||
| Explanation | Characteristics and Tribological Behavior of Hexagonal Boron Nitride | Toshiyuki SAITO | 8 | 539 | |
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | My Experience Note through Study Abroad at INSA de Lyon | Kazuyuki YAGI | 8 | 546 |
No.9 Special Issue on Ethics and Intellectual Property for Engineers
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | “Tribology” That Is “Technology” to Be Used a Lot | Fumihiko YOKOYAMA | 9 | 557 |
| Record | Tribology — Its Birth and Growth for 50 Years | Yoshitsugu KIMURA | 9 | 558 | |
| Special Issue on Ethics and Intellectual Property for Engineers | Prologue to the Special Issue on “Ethics and Intellectual Property for Engineers” | Shingo WASHIKA | 9 | 562 | |
| Explanation | Why Engineer Ethics Are Required? —Science and Technology— | Takeshi OWA | 9 | 563 | |
| Commitment and Well-Being of Engineers —How to Make Students Notice and Consider— | Yoshio KATAKURA | 9 | 569 | ||
| Researcher Ethics and Copyright Act | Shusaku ITO | 9 | 575 | ||
| Approaches of Japanese Society of Tribologists to Ethics Issues | The Ethics Committee in JAST | 9 | 582 | ||
| Protection of Trade Marks —Trade Marks under Trademark Law and Requirements of Registration— | Yoko SOMEYA | 9 | 587 | ||
| Basic Knowledge of Patent System for Engineers —For Correct Use of Research and Development Results— | Tatsushi GOCHO | 9 | 593 | ||
| Basis of Patent Search with Japan Platform for Patent Information | Koichi SEGAWA and Shingo WASHIKA | 9 | 601 | ||
| Report | Influence of Load and Lubricant on the Life of Rolling Bearing | Technical Committee on Life of Rolling Bearing | 9 | 607 | |
| Original Contribution | Study of ZnDTP Degradation Controlled by Low Treatrate Metallic Detergents and the Mechanism | Akiko FUJII, Akimitsu FUJIWARA, Mitsuhiro NAGAKARI and Eiji NAGATOMI | 9 | 615 | |
| Low-Friction Boundary Lubrication Properties of Metal-Containing Hydrogen-Free Diamond-Like Carbon Films under Poly-Alpha-Olefin Lubricant | Takanori SHINDO, Yuta SAITO and Shojiro MIYAKE | 9 | 627 | ||
| Influence of Loading Rate on Running-In Behavior in the Combination of Diamond-Like Carbon Film and FC230 Cast Iron | Tomomi HONDA, Keitaro YOSHIDA, Toshiro MIYAJIMA, Yoshiro IWAI, Takatoshi SHINYOSHI and Yoshio FUWA | 9 | 636 |
No.10 Special Issue on Progress and Prospect of Tribology in Commemoration of the 60th Anniversary of JAST (Part 1)
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | The Most Chaotic Tribology | Akemi ITO | 10 | 651 |
| Special Issue on Progress and Prospect of Tribology in Commemoration of the 60th Anniversary of JAST (Part 1) | Prologue to the Special Issue on “Progress and Prospect of Tribology in Commemoration of the 60th Anniversary of JAST” | Minoru NONOGAKI and Takeshi NAKATSUJI | 10 | 652 | |
| Explanation | Contributions of Tribology to Progress in the Japanese Industry | Yoshitsugu KIMURA | 10 | 653 | |
| Progress and Prospect of Tribology in Magnetic Recording Disk Storage | Norio TAGAWA, Hiroshi TANI and Shinji KOGANEZAWA | 10 | 659 | ||
| Progress and Prospect of Lubricant Technologies | Hitoshi HAMAGUCHI | 10 | 665 | ||
| Progress and Prospect of Surface Modification Technologies | Shinya SASAKI | 10 | 673 | ||
| Progress and Prospect of DLC Coating Applied Technologies to Automotive Engine Component | Makoto KANO | 10 | 680 | ||
| Lecture of Tribology | Lecture | Basic Knowledge of Surface Texture and Surface Roughness, Part 1 —Measurement of Surface Roughness：Measuring Conditions and etc. of Contact Stylus Instruments— | Ichiro YOSHIDA | 10 | 687 |
| The Tribo-Soshi, Essays from Tribologists | Essay | An Introduction to Tribo-Contact Mechanics | Kazunori ICHIMARU | 10 | 693 |
| Original Contribution | Effects of Transition Point of Viscoelasticity of Diurea Grease and Molecular Structure of Thickener on Running Torque of the Ball Bearing —Effects of the Alkyl Chain Length of Aliphatic Diurea— | Mariko NITTA, Takeshi TSUDA, Hirokazu ARAI, Kiyomi SAKAMOTO and Kazumi SAKAI | 10 | 699 | |
| Relation between Color of Membrane Patches and Oxidation Processes of Non-Additive Mineral Oil for the Turbine | Tomohiko KON, Tomomi HONDA, Akira SASAKI and Kenji MATSUMOTO | 10 | 709 |
No.11 Special Issue on Progress and Prospect of Tribology in Commemoration of the 60th Anniversary of JAST (Part 2)
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Simple, This is My Favorite Phrase | Shinya KONDO | 11 | 719 |
| Special Issue on Progress and Prospect of Tribology in Commemoration of the 60th Anniversary of JAST (Part 2) | Explanation | A Historical Overview of Progress in Hydrodynamic Lubrication Theory | Tsunamitsu NAKAHARA | 11 | 720 |
| History of Technologies for Gas Bearings | Atsunobu MORI and Hiroshi YABE | 11 | 728 | ||
| Progress and Prospect of Technologies for Rolling Bearings | Kazunori HAYASHIDA and Hiroki MATSUYAMA | 11 | 734 | ||
| Progress and Prospect of Constant Velocity Joints and Axle Bearings —Low Fuel Consumption for Vehicles by Light Weight and Low Friction Technologies— | Shuji MOCHINAGA, Makoto SEKI and Takuji KOBAYASHI | 11 | 742 | ||
| Plain Bearings for High-Speed Rotating Machinery | Masato TANAKA | 11 | 749 | ||
| Progress and Prospect of Marine Engine Bearings | Arihiro YOSHIDA, Motohira YAMADA, Takashi ANDO, Yoshiaki SATO and Tadashi TANAKA | 11 | 757 | ||
| Progress and Prospect of Crankshaft Bearings in Automotive Engines | Yoshio KUMADA | 11 | 763 | ||
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | Report on Malaysian International Tribology Conference 2015 | Satoru MAEGAWA | 11 | 771 |
| Original Contribution | Evaluation of the Surface Strength of WC-Co Alloy by a Micro Slurry-Jet Erosion (MSE) Test —Discussion on Erosion Mechanism by Debris Analysis— | Takuya TAKAZAWA and Yoshiro IWAI | 11 | 775 | |
| In Situ Observation of Transient Responses in Grease Lubrication by a Micro Infrared Spectroscopy | Yasushi HOSHI, Koji TAKIWATARI, Hidetaka NANAO and Shigeyuki MORI | 11 | 784 |
No.12 Special Issue on Tribology on Snow and Ice
| Special Issues | Category | Title | Authors | No. | Page |
|---|---|---|---|---|---|
| Messages to Tribologists | Serial | Future in Automotive Technology and Tribology | Takumaru SAGAWA | 12 | 795 |
| Special Issue on Tribology on Snow and Ice | Prologue to the Special Issue on “Tribology on Snow and Ice” | Toshikazu FUJINO | 12 | 796 | |
| Explanation | History and Trends of Tribology on Ice and Snow | Katsutoshi TUSIMA | 12 | 797 | |
| Friction on Snow Avalanche Formation and Dynamics | Yoichi ITO and Isao KAMIISHI | 12 | 804 | ||
| Snow Removal Machinery and Tribology —For Rational Design Based on Dynamic Simulation Analysis— | Masajiro ABE | 12 | 810 | ||
| New Developments in Snow and Ice Accretion Prevention Technology with Low-Friction | Kenji YANAGISAWA | 12 | 819 | ||
| Shitamachi Bobsleigh Network Project —Challenge to the World by Small-Scale Companies in Ota City— | Reiji SAKATA | 12 | 825 | ||
| The Tribo-Soshi, Essays from Tribologists | Essay | Encountering to Diverse World in Biotribology | Teruo MURAKAMI | 12 | 831 |
| Essay for Overseas Experience in Tribology —Around the World— | Up-to-date News | Report on the 2015 STLE Tribology Frontiers Conference | Masaaki MIYATAKE | 12 | 835 |
| Original Contribution | Energy Dissipation in Contact of Rough Metallic Surfaces under Normal Loading | Tomoya NAKAMURA, Satoshi TAKADA and Joichi SUGIMURA | 12 | 838 | |
| Molecular Dynamics Simulation of Sliding Process Considering Experimental Results of Nanocontact and Influence of Oxide Film | Jun SHIMIZU, Libo ZHOU, Teppei ONUKI, Hirotaka OJIMA, Hirotaka MIWA and Toshikazu NANBU | 12 | 845 | ||
| Tribological Properties of Sintered Bronze Containing Micro-Sized Sulfide | Yoshimasa HIRAI, Tomohiro SATO and Hatsuhiko USAMI | 12 | 857 | ||
| Study on Tribological Properties of Polyisobutylene Lubricant for Use in Screw Tightening | Takefumi OTSU, Kyoichi KOMATSU and Shinji HASHIMURA | 12 | 866 | ||
| Film Thickness and Traction in Soft EHL with Grease | Tsuyoshi KOCHI, Ryosuke ICHIMURA, Michitaka YOSHIHARA, Daming DONG and Yoshitsugu KIMURA | 12 | 874 | ||
| Influences of Squareness Error at Bolt Bearing Surface on a Frictional Coefficient between Bearing Surfaces and on Tightening Accuracy | Shinji HASHIMURA, Hayato ITO, Kyoichi KOMATSU and Takefumi OTSU | 12 | 882 |
