Keiji Yamada

Last Updated :2025/04/22

Affiliations, Positions
Graduate School of Advanced Science and Engineering, Professor
E-mail
keijihiroshima-u.ac.jp
Self-introduction
I am a professor whose research field is Machining Technology.

Basic Information

Academic Degrees

  • Doctor of Engineering, Kanazawa University
  • Master of Engineering, Kanazawa University

Educational Activity

  • [Bachelor Degree Program] School of Engineering : Cluster 1(Mechanical Systems, Transportation, Material and Energy) : Program of Mechanical Systems Engineering
  • [Master's Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Mechanical Engineering Program
  • [Doctoral Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Mechanical Engineering Program

Research Fields

  • Engineering;Mechanical engineering;Production engineering / Processing studies

Research Keywords

  • Machiniing, Laser machining

Educational Activity

Course in Charge

  1. 2025, Liberal Arts Education Program1, 4Term, Industry and Technology
  2. 2025, Liberal Arts Education Program1, 2Term, Design and Optimization of Mechanical Systems
  3. 2025, Undergraduate Education, 3Term, Introduction of Mechanical and Transportation Engineering
  4. 2025, Undergraduate Education, Second Semester, Machine Design and Drawing
  5. 2025, Undergraduate Education, 3Term, Machine Design
  6. 2025, Undergraduate Education, 4Term, Measurement Signal Processing
  7. 2025, Undergraduate Education, Year, Graduation Thesis
  8. 2025, Graduate Education (Master's Program) , 1Term, Special Exercises on Mechanical Engineering A
  9. 2025, Graduate Education (Master's Program) , 2Term, Special Exercises on Mechanical Engineering A
  10. 2025, Graduate Education (Master's Program) , 3Term, Special Exercises on Mechanical Engineering B
  11. 2025, Graduate Education (Master's Program) , 4Term, Special Exercises on Mechanical Engineering B
  12. 2025, Graduate Education (Master's Program) , 1Term, Special Exercises on Mechanical Engineering B
  13. 2025, Graduate Education (Master's Program) , 2Term, Special Exercises on Mechanical Engineering B
  14. 2025, Graduate Education (Master's Program) , Academic Year, Special Study on Mechanical Engineering
  15. 2025, Graduate Education (Master's Program) , 1Term, Advanced Precision Machining
  16. 2025, Graduate Education (Doctoral Program) , Academic Year, Special Study on Mechanical Engineering

Research Activities

Academic Papers

  1. Enhanced Multi-Stage Laser Forming Path Prediction through Transfer Learning and Imaginary data Validation, The International Journal of Advanced Manufacturing Technology, 20250421
  2. Chip Loading on Electroplated Diamond Wheels in Trimming Process for CFRPs and Effects by In-process Laser Dressing, Journal of Advanced Mechanical Design, Systems, and Manufacturing, 202410
  3. Machine learning for scanning path prediction in laser forming - Application of structured patterns and CNN -, Journal of Laser Micro/Nanoengineering, 19(2), 202405
  4. Study on cutting forces in zero-cutting after complete stop of feed motion when face milling of alloy 718, International Journal of Abrasive Technology, 11(3), 175-183, 20230512
  5. Modeling of Deep Learning Applications for Chatter Detection in the Milling Process, Procedia CIRP, 118, 471-476, 2023
  6. A machine learning approach for simulation of multi-stage laser forming process, JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, 17(1), 1-14, 20230101
  7. Prediction of Surface Roughness Components in Turning with a Single Point Tool -Measurement of Tool Edge Contour and Prediction of its Position during Cutting, International Journal of Automation Technology, 18(1), 1-11, 20240105
  8. Effect of Cutting Fluid on Tool Wear in Finished Surface Formation Area of Rounded Nosed Tool When Turning Alloy 304, International Journal of Automation Technology, 16(5), 528-535, 20220905
  9. CHIP LOADING CAUSED ON ELECTROPLATED DIAMOND WHEELS IN GRINDING PROCESS FOR CFRPS, Proceedings of the 2022 International Symposium on Flexible Automation, 13-14, 20220704
  10. The Effect of Noise onto HHT Features for Face Milling Cutter Condition Monitoring, Journal of Physics: Conference Series, 1845(1), 20210301
  11. Static Analysis of Railway Axle using Finite Element Method and Monitoring of Railway Bearing Based on Vibration Analysis, Journal of Physics: Conference Series, 1845(012037), 20210301
  12. Machine Learning of Laser Forming Simulator for Multi-stage Forming, Proc. of 10th International Conference on Leading Edge Manufacturing in 21st Century, 325-330, 20211114
  13. Effect of lubricant on tool wear in finished surface formation area of rounded nosed tool, Proc. of 10th International Conference on Leading Edge Manufacturing in 21st Century, 185-188, 20211114
  14. Performance evaluation method for cutting fluids using cutting force in micro-feed end milling, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 62, 232-243, 202003
  15. Hilbert-Huang Transform Analysis of Machining Stability in Ball-nose End-milling of Curved Surface, International Journal of Automation Technology, 14(3), 500-511, 20200501
  16. Tool wear mechanism in up-cut end milling of AISI 1050 at different feed rates, JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, 14(3), 2020
  17. Planetary motion cross bar friction test for application in machining process, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 62, 143-150, 202003
  18. Chatter identification in turning process based on vibration analysis using Hilbert-Huang transform, JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES, 14(2), 6856-6868, 20200623
  19. Influence of Tool Posture and Position on Stability in Milling with Parallel Kinematic Machine Tool, International Journal of Precision Engineering and Manufacturing, 21, 2359-2373, 202012
  20. Improved Machinability of High Hardened Die Steel by Using Pulsed Laser Surface Treatment, International Journal of Precision Engineering and Manufacturing, 20(10), 1667-1676, 20190629
  21. Experimental Study on the Relationship between Direction of Crack Propagation and Thermal Stress Distribution in Laser Cleaving Process for Glass Substrate, Journal of Laser Micro/Nanoengineering, 14(2), 161-167, 201910
  22. Evaluation Method for Friction Coefficient of Machining Fluids Using Cutting Force in Micro Feed End Milling, Applied Mechanics and Materials, 894, 158-163, 201909
  23. Effects of Preheating Temperatures at Primary Shear Zone in Laser Assisted Milling Process, Key Engineering Materials, 825, 45-50, 201910
  24. Analysis of Transient Signal using Hilbert-Huang Transform for Chatter Monitoring in Turning Process, Proc. of ICITISEE2019, 20191102
  25. ★, Application of Hilbert–Huang Transform for Vibration Signal Analysis in End-milling, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 53, 263-277, 2018
  26. Milling Process Monitoring Based on Vibration Analysis Using Hilbert-Huang Transform, International Journal of Automation Technology, 12(5), 688-698, 20180905
  27. Wear mechanism of coated tools in the turning of having wide range of tensile strength ductile cast iron, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 47, 46-53, 201701
  28. ★, Photoelastic observation of stress distributions in laser cleaving of glass substrates, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 47, 333-343, 201701
  29. Relationship between Cutting Heat and Tool Edge Temperature in End Milling of Titanium Alloy, Key Engineering Materials, 749, 15-20, 201708
  30. Wet Core Drilling of CFRP with an Electrodeposited Diamond Core Drill - Effects of Cutting Conditions on Chip Evacuation and Core Jamming, Key Engineering Materials, 749, 58-64, 201708
  31. Difference of Feed Marks in Cutting Fluids when Turning Stainless Steel, Key Engineering Materials, 749, 111-117, 201708
  32. Wear Characteristics of Coated Carbide Tools in the Face Milling of Ductile Cast Iron, Key Engineering Materials, 749, 178-184, 201708
  33. Study of comparing cutting force signal features for dry, air cooling and minimum quantity lubrication (MQL) drilling, JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, 11(2), 2017
  34. Effect of coating layer loss on the wear rate change of coated carbide tools in turning process, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 50, 1-7, 201710
  35. A new quantitative evaluation for characteristic of surface roughness in turning, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 50, 20-26, 201710
  36. Machinability of spheroidal graphite cast irons with different properties i structure and strength, Journal of the Japan Society for Abrasive Technology, 61(3), 139-144, 201703
  37. Drilling of CFRP with an Electrodeposited Diamond Core Drill – Effects of Air Assistance and Tool Shape –, International Journal of Automation Technology, 10(3), 310-317, 20160502
  38. Pulsed Laser Surface Treatment for Improvement of Machinability, Key Engineering Materials, 725, 641-646, 2016
  39. Stability of Adhered Material to the Cutting Edge of a Cermet Insert in Turning of an Austenitic Stainless Steel, Key Engineering Materials, 656-657, 363-368, 20150401
  40. Machine Learning of Cutting Conditions in Drilling Using Artificial Neural Network, Key Engineering Materials, 656-657, 328-334, 20150401
  41. Influence of the Cutting Fluid on Tool Edge Temperature in End Milling of Titanium Alloy, Key Engineering Materials, 656-657, 261-265, 20150401
  42. Basic Study on Thermo Chemical Turning Method for Metal Bonded Diamond Wheels, Key Engineering Materials, 656-657, 180-184, 20150401
  43. Photoelastic observation of thermal stress in laser cleaving of hard brittle materials, Proc. of 8th International Conference on Leading Edge Manufacturing in 21st Century, 20151019
  44. Wear characteristics of coated carbide tools in the turning of ductile cast iron, Proc. of 8th International Conference on Leading Edge Manufacturing in 21st Century, 20151019
  45. Influence of coating material on the curl of chip in tapping, Proc. of 8th International Conference on Leading Edge Manufacturing in 21st Century, 20151019
  46. Study of chatter characteristics on thin-walled turning, Proc. of 8th International Conference on Leading Edge Manufacturing in 21st Century, 20151019
  47. Comparison of applying static and dynamic features for drill wear prediction, JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, 8(4), 20140601
  48. Effect of different features to drill-wear prediction with back propagation neural network, PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY, 38(4), 791-798, 20141001
  49. Permeability control method with laser for porous bushings of aerostatic bearings, INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING, 14(5), 779-784, 20130601
  50. A Basic Study on the Relations between Machining Conditions and the Static & Dynamic Components of Forces in Drilling, International Journal of Automation Technology, 7(3), 345-352, 20130501
  51. Applying Constant Pressure Unit to Ductile Mode Cutting of Hard and Brittle Materials, International Journal of Automation Technology, 7(3), 278-284, 20130501
  52. Drill Wear Prediction with Features Extracted From the Static & Dynamic Components of Forces by Wavelet Packet Transform Using Back Propagation Neural Network, Proceedings of International Conference on Leading Edge Manufacturing in 21st century, 452-456, 20130501
  53. ★, A Study on Aspects of Attrition Wear of Cutting Grains in Grinding Process, INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING, 12(6), 965-973, 20111201
  54. Production of Hard Materials with Ubiquitously Fe-B System by Spark Sintering and their Characteristics, 58(8), 487-494, 20110801
  55. Turning of aluminium alloy with an amorphous silicon-carbide coated tool, Journal of the Japan Society for Abrasive Technology, 54(4), 230-235, 20100401
  56. Forming of Microstructure on Hard Brittle Materials in Ductile Mode Cutting, Key Engineering Materials, 447-448, 91-95, 20100601
  57. Evaluation of Adhesino on Tool-Chip Interface with Dynamic Components of Cutting Force, Journal of the Japan Society for Precision Engineering, 76(8), 926-932, 20100801
  58. Micro Machining of Silicon by Second-Harmonic Pulsed Nd:YAG Laser-- Application of Microlens Fabricated by Thermal Deformation Method as Optical System for Laser Machining --, Journal of the Japan Society for Precision Engineering, 76(11), 1283-1287, 20101101
  59. Laser Cleaving of Wafers for Electric Devices, Journal of the Japan Society for Precision Engineering, 75(3), 443-445, 20090301
  60. Influence of Additional Electrical Current on Machinability of BN Free-Machining Steel in Turning, Journal of Advanced Mechanical Design, Systems, and Manufacturing, 26(2), 171-178, 20090701
  61. ★, Dental Treatment with Laser Beam ---Monitoring Enabling Safe Hard-Tooth-Tissue Removal ---, International Journal of Automation Technology, 3(5), 494-501, 20090901
  62. New Detecting Method for Chips Jammed in Spindle Tool-holder Interface, Journal of the Japan Society for Precision Engineering, 75(10), 1250-1254, 20091001
  63. The Relationship between Dynamic Components of Cutting Force and Adhesion of Tool-Chip Interface, Key Engineering Materials, 407-408, 469-472, 20090401
  64. Mirror Finishing of Austenitic Stainless Steel with a Cermet Insert, Key Engineering Materials, 407-408, 384-387, 20090401
  65. Laser-assisted Truing for Metal-bonded Diamond Wheel, Key Engineering Materials, 407-408, 122-125, 20090401
  66. New Method for Controlling Air Permeability of Porous Metal with Laser, Asian Symposium for Precision Engineering and Nanotechnology 2009, 2C5, 20091101
  67. Transfer of Tool Geometry onto the Machined Surface in Continuous Turning of Adhesive Metals, Asian Symposium for Precision Engineering and Nanotechnology 2009, 2B5, 20091101
  68. Detection of chatter by the measurement of acceleration of the spindle head in the axial direction, Proc. of the Leading Edge of Manufacuturing in 21th century, 161_14-06, 20091201
  69. Influence of Additional Electrical Current on Machinability of BN Free-Machining Steel in Turning, JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, 3(2), 171-178, 2009
  70. Study on Dental Treatment with YAG Laser (3rd Report) --- Effects of Water on Cavity Preparation ---, Journal of the Japan Society for Precision Engineering, 74(2), 150-154, 20080201
  71. Development of a mist-sensor for MQL machining and effects of pattern of jetted oli mist on drill wear, Journal of the Japan Society for Abrasive Technology, 52(9), 525-530, 20080901
  72. Effects of MQL on Drilling (1st Report) --- Features of Drilled Hole ---, Journal of the Japan Society for Precision Engineering, 73(2), 232-236, 20070201
  73. Machinability of Steels After Heat Treatment with CO2 Laser and Its Improvement, 73(727), 879-884, 20070401
  74. Thermal Damage of Silicon Wafer in Thermal Cleaving Process with Pulsed Laser and CW Laser, Proc. of Photonics West 2006: Lasers and Applications in Science and Engineering, 20060101
  75. ★, Effect of Oil Mist on Tool Temperature in Cutting, Trans. of the ASME= J. of Manufac. Sci. and Eng., 128(1), 130-135, 20060201
  76. Study on Cleaving Process od Silicon Wafer with Nd:YAG Laser - Effect od Refrigerating Chuck System -, Journal of the Japan Society for Precision Engineering, 72(3), 393-397, 20060301
  77. Reduction of Adhesion with an Amorphous Silicon Coated Tool, Progress of Machining Technology (Proc. of 8th. Int. Conf. on Progress of Machining Tech.), 205-208, 20061101
  78. Tool Wear under High-speed End Milling of Ti-6Al-4V Alloy, Material Scinence and Technology (MS&T) 2006, Product Manufacturin, 255-263, 20060901
  79. On-Machine Evaluation Method for Misengagement of Toolholder by Inclusion of Chips, Proc. 8th Int. Conf. on Progress of Machining Technology, 57-60, 20061101
  80. Visualizing and Measuring of Splayed Mixture with Optical Dispersion Method for MQL Drilling, Proc. 8th Int. Conf. on Progress of Machining Technology, 297-300, 20061101
  81. Basic Study on Laser Forming (2nd Report), Journal of the Japan Society for Precision Engineering, 71(4), 481-485, 20050401
  82. Temperature Measurement in Laser Forming of Sheet Metal, Annals of the CIRP, 54(1), 179-182, 20050801
  83. Hardmilling with CBN and Coated Tools, Proc. of the Third Int. Conf. on Leading Edge Manufacturing in 21st. Century, 497-500, 20051001
  84. Studies on High-Speed Milling with Small Ball End Mill --- Temperature Distribution on Flank of Cutting Tool ---, Journal of the Japan Society for Precision Engineering, 70(12), 1527-1532, 20041201
  85. Monitoring of Dental Treatment with Laser by Measurement of Sound, 15(2), 61-66, 20040901
  86. Monitoring of Thermal Damages by Means of Spectroscopic Analysis in Cavity Preparation with Laser, 15(1), 1-5, 20040301
  87. Evaluation of Grinding Wheel Surface by Means of Grinding Sound Discrimination, JSME Int. Journal Ser. C, 47(1), 52-58, 20040301
  88. Thermal Stress Cleaving with Pulsed YAG Laser as New Dicing Method of Silicon Wafer, Proc. of 4th. Asian Pacific Laser Symposium, CD-ROM, 20040301
  89. Rapid Fabrication of Various-shape Microlens by Laser-induced Deformation, Proc. of 4th. Int. Conf. of EUSPEN, 57-58, 20040501
  90. Fabrication of Cylindrical Plastic Microlens Using Er:YAG Laser Beam -Influence of Process Parameter-, Proc. 5th Int. Sym. on Laser Precision Microfabrication, 243-248, 20040501
  91. Laser Dressing of Metal-Bonded Diamond Wheel, Proc. of ASPE 19th. Annual Meeting, 20041001
  92. Influence of Temperature and Process Parameters on Bending Angle in Laser Forming, Proc. 6th Int. Conf. on Progress of Machining Technology, 354-359, 20041201
  93. Effect of Additional Current on Cutting Mechanism of Free Machining Steels in Turning, Progress of Machining Technology (Proc. of 7th. Int. Conf. on Progress of Machining Tech.), 786-791, 20041201
  94. Fabrication of Plastic Microlens by Thermal Deformation Induced with Laser, Journal of the Japan Society for Precision Engineering, 69(10), 1487-1491, 20031001
  95. Discrimination of Grinding Wheel Surface by Means of Neural Network Technique --- Studies on In-process Evaluation of Grinding Wheel Surface ---, Journal of the Japan Society for Precision Engineering, 69(2), 258-262, 20030201
  96. Cleaving Process of Brittle Materials with Pulsed YAG Laser --- Thermal Stress Analysis in Cleaving Process of Silicon Wafer ---, Journal of the Japan Society for Precision Engineering, 69(1), 120-124, 20030101
  97. Influences of Temperature on Bending Angle in Laser Forming Process, Proc. of Int. Conf. on Leading Edge Manufacturing in 21st Century, 885-890, 20031101
  98. Evaluation of Grinding Wheel Surface by Means of Grinding Sound Discrimination, Proc. of Int. Conf. on Leading Edge Manufacturing in 21st Century, 234-246, 20031101
  99. Study on Dental Treatment with YAG Laser (2nd Report) --- Comparison between Nd:YAG Laser and Er:YAG Laser ---, Journal of the Japan Society for Precision Engineering, 68(12), 1580-1584, 20021201
  100. Thermal Stress Cleaving of Brittle Materials by Laser Beam, Annals of the CIRP, 51(1), 149-152, 20020801
  101. Investigation of Temperature at Tool-chip Interface in Turning Using Two-color Pyrometer, Trans. of the ASME= J. of Manufac. Sci. and Eng., 124(2), 200-207, 20020501
  102. Effects of Water-solutin Type Coolant in Superfinishing of Superalloy, Journal of the Japan Society for Precision Engineering, 68(3), 430-434, 20020301
  103. ★, Studies on Cleaving Mechanism of Silicon Wafer with Pulsed YAG Laser, Journal of the Japan Society for Precision Engineering, 67(11), 1861-1865, 20011101
  104. Temperature on Flank Face of Cutting Tool in High Speed Milling, Annals of the CIRP, 50(1), 37-40, 20010801
  105. Basic Study on Laser Forming, Journal of the Japan Society for Precision Engineering, 67(2), 300-305, 20010201
  106. Temperature of Tool Flank in Intermitting Cutting --- Studies on High Speed Endmilling (1st Report) ---, Journal of the Japan Society for Precision Engineering, 66(11), 1786-1791, 20001101
  107. Study on Dental Treatment with YAG Laser (1st Report) --- Temperature of Dental Tissue Irradiated with Laser Beam ---, Journal of the Japan Society for Precision Engineering, 66(9), 1388-1393, 20000901
  108. Studies on Temperature in Laser Forming Process, Proc. of 8th. Int. Conf. on Sheet Metal, 313-322, 20000401
  109. Effect of Cooling Methods on Grinding Temperature, Proc. 6th Int. Conf. on Progress of Machining Technology, 381-387, 20000901
  110. Temperature Measurement of CBN Tool in Turning of High Hardness Steel, Annals of the CIRP, 48(1), 63-66, 19990801
  111. Measurement of Tool-Chip Interface Temperature in Turning Using Two-color Pyrometer, Transactions of the Japan Society of Mechanical Engineers Series C, 65(633), 2094-2101, 19990501
  112. ★, Temperature and Absorptivity of Workpiece in CO2 Laser Processing, Journal of the Japan Society for Precision Engineering, 65(1), 126-130, 19990101
  113. Measurement of Temperature of CBN Tool in Turning of High Hardness Steel, Journal of the Japan Society for Precision Engineering, 64(11), 1684-1688, 19981101
  114. Measurement of Interface Temperature between a Cutting Tool and a Chip in Turning Using Two-color pyrometer, Proceedings of the 3rd International Symposium on Advanced and Aerospace Science & Technology in Indonesia, 2, 401-408, 19980801
  115. Evaluation of Mechanical Properties of DLC Film with Molecular Dynamics Simulation --- Evaluation of Hardness by Analysis of Identification Behavior ---, Journal of the Japan Society for Precision Engineering, 63(12), 1735-1740, 19971201
  116. Temperature of Work Materials Irradiated with CO2 Laser, Annals of the CIRP, 46(1), 117-122, 19970801
  117. Studies on Thermal Partition Coefficients in Surface Grinding of Steel, Journal of the Japan Society for Precision Engineering, 60(11), 1616-1620, 19941101
  118. ★, Measurement of Grinding Temperature of Ceramics Using Infrared Radiation Pyrometer with Optical Fiber, Trans. of the ASME= J. of Eng. for Industry, 114(3), 317-322, 19920801
  119. Measurement of Grinding Temperature of Sintered SiC Ceramics by a Pyrometer Using Chalcogenide Optical Fiber, Journal of the Japan Society for Precision Engineering, 56(9), 1683-1685, 19900901
  120. Measurement of Grinding Temperature of Sintered Si3N4 Ceramics by a Pyrometer Using Fluoride Optical Fiber, Journal of the Japan Society for Precision Engineering, 56(8), 1452-1455, 19900801

Awards

  1. 2011/03/15, JSPE Best Paper Awards, 精密工学会

Patented

  1. Patent, JP4888858, 2011/12/22
  2. Patent, 2004/06/10
  3. Patent, 2003/09/24
  4. Patent, 2004/01/29