Kyushu University Academic Staff Educational and Research Activities Database
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Takashi OKAYASU Last modified date:2019.06.18

Associate Professor / Bioproduction Environmental Sciences
Department of Agro-environmental Sciences
Faculty of Agriculture


Graduate School
Undergraduate School
Other Organization


E-Mail
Homepage
http://www-mech.bpes.kyushu-u.ac.jp/
The goals and objectives of the Bioproduction Engineering are to develop the high productivity and the high quality of agricultural products by mechanizing and optimizing the farm work. Therefore, the technologies for development of high productivity by the improvement of the energy powers, the farm machinery and the cultivation systems with the information science is mainly studied. .
Academic Degree
Ph.D.
Field of Specialization
Agricultural Machinery
Outline Activities
1. DEVELOPMENT OF SOIL TILLAGE SIMULATOR USING FEM-DEM QUASI-COUPLING METHOD
Soil tillage simulator was developed by the FEM (Finite Element Method) - DEM (Discrete Element Method) quasi-coupling method. By using this simulator, not only the prediction of the soil dynamics such as soil cutting, crushing, reversing, and throwing and the soil reaction forces acting on the tillage tool but also the evaluation of stress and strain distribution in the tillage tool during the soil tillage operation are carried out. We are also trying to improve the accuracy in the development of proper constitutive models for describing the mechanical behavior of soils and metals, and the accurate modeling of tillage tools using 3D scanner and CAD.

2. DEVELOPMENT OF INFORMATIZATION AGRICULTURAL SUPPORTING SYSTEM AND EVALUATION OF ITS VALIDITY
The informatization agricultural supporting system called the “Agri-eye” is developed to optimize the agricultural production system. This system is composed of the field environmental monitoring and acquisition, the crop growth diagnosis and quality evaluation, the work history recording, the data analysis and visualization, the communication tools, and so on. Currently more than 50 devices have been already installed into more than 10 real fields mainly distributed in Fukuoka and Oita prefectures. The validity of the systems has been verified by the feasibility studies up to present.

3. UTILIZATION OF ICT IN TROPICAL AGRICULTURE
Environmental information is important factor affecting the agricultural production system. In four season countries including Japan, a weather condition during cultivations will be controlled by using a greenhouse and environmental control facilities. However, in tropical countries like Indonesia and Bangladesh, a utilization of the automatic environmental control system is still rare because of the operational costs and the economic reasons. Thus, we try to utilize the Information and Communication Technology (ICT) in order to improve the agricultural production system in the tropical agriculture. In this study, the simple field monitoring systems have been developed and installed into the real tropical fields in Indonesia and Bangladesh. These information measured are utilized to establish the real-time environmental evaluation and the decision support on the farm operations.
Research
Research Interests
  • Study of Plant Phenotyping
    keyword : Plant Phenotyping, Plant Body Sensing, High Throughput Processing, Image Processing and Analysis, IoT
    2014.04.
  • Study on Smart Agriculture
    keyword : Smart Agricultre, Precision Agriculture, ICT, IoT, Field Monitoring System, GIS, Hyperspectral Imaging, Open software, Virtual and Augmented Reality
    2005.06.
  • Study on numerical analyses of mechanical behavior in crop-machine system
    keyword : Crop, Biomechanics, Inelastic behavior, Discrete Element Method (DEM), Finite Element Analysis (FEM)
    2005.06.
  • Study on analysis of soil defomation behavior by elastoplastic FEM
    keyword : Subloading surface model, Elastoplastic finite element method, Cyclic loading, Soil compaction, Optimal design
    2002.09.
  • Study on elastoplastic constitutive equation of materials
    keyword : Elastoplastic, Rate (time)-dependency, Creep, Stress relaxation, Subloading surface model, Structure
    2002.01.
  • Study on experimental and theoretical analyses for frictional phenomena between structures
    keyword : Frictional phenomenon, Subloading surface concept, Sliding, Cyclic friction
    2002.04~2008.03.
  • Development of soil displacement measurement system based on PIV
    keyword : PIV (Particle Image Velocimetry), Soil deformation, Soil compaction, Wheel, Online measurement system
    2002.01.
  • Study on traveling performance of off-road vehicle and soil deformation
    keyword : Drawbar pull, Traveling resistance, Trafficability, Tractive performance
    1996.04.
Academic Activities
Books
1. Takehiko Hoshi, Ken-Ichiro Yasuba, Hideto Kurosaki and Takashi Okayasu, Ubiquitous Environment Control System: An Internet-of- Things–Based Decentralized Autonomous Measurement and Control System for a Greenhouse Environment, IntechOpen, 10.5772/intechopen.71661, 107-123, 2018.03.
2. Takashi Okayasu, Andri Prima Nugroho, Daisaku Arita, Takashi Yoshinaga, Yoshiki Hashimoto, Rin-ichiro Tachiguchi, Smart Sensors at the IoT Frontier -Sensing and Visualization in Agriculture with Affordable Smart Devices-, Springer, 299-325, 2017.06.
Reports
1. Takashi OKAYASU, Informatization Agriculture in Japan, Proceedings of the International Symposium on Agricultural and Biosystem Engineering (ISABE) 2013, 8pages, 2013.08, Agriculture is dependent on climate, weather, soil conditions, and crop types. Therefore, farmers have tried to develop and improve their own cultivation techniques and senses during the long-term experiences so as to fit the peripheral field environment. Information Communication Technology (ICT) is currently applied in several fields of agriculture to improve the agricultural productivity and cultivation skills. There are many kinds of ICT-agriculture applications that already used for supporting the agricultural production such as environmental monitoring, precision agriculture including spatial data collection, precision irrigation and supplying data to farmers, facility automation including greenhouse control and animal-feeding facility (Wang, 2006).
On the other hand, authors have tried to develop the informatization agricultural supporting system called “Agri-eye” to optimize the agricultural production system (Okayasu et al., 2010). This system is composed of field environmental monitoring and acquisition, crop growth diagnosis and quality evaluation, work history recording, data analysis and visualization, and communication tools, and so on. The field environmental monitoring devices above 50 have been installed in the fields above 10 mainly in the Fukuoka and the Oita prefectures. The work recording system has been also distributed over the Internet and can be utilized through the web browsers on personal computers, mobile phones, and smartphones. The validity of the systems has been verified by the feasibility studies up to present.
In this article, several application examples of the informatization agriculture in Japan will be introduced here..
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Papers
1. T. Okayasu, D. Arita, T. Yoshinaga, A. Shimada, R. Taniguchi, E. Inoue, Y. Hirai, and M. Mitsuoka, Development of plant phenotyping platform using affordable devices and sensors, Proc. AFITA/WCCA2018 , 4 pages, CD-ROM, 2018.10.
2. Nugroho A.P., Sutiarso, L., Masithoh, R.E., Okayasu, T., Development of Plant Motion Monitoring System to Study The Circadian Rhythms Based on Leaf Motion Implementing the Optical Flow Method, Proceedings of the 9th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB), 1-7, 2018.05.
3. Okayasu, T., Arita, D., Yoshinaga, T., Taniguchi, R., Inoue, E., Hirai, Y., Mitsuoka, M., Development of Monorail-type Mobile Robot for Field Environment and Plant Status Monitoring, Proceedings of the 9th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB), 1-6, 2018.05.
4. Ibrahim, M.N.R., Okayasu, T., Yoshimura, A., Yamagata, Y., Furuya, N, Inoue, E., Hirai, Y., Mitsuoka, M., Early Disease Detection of Bacterial Leaf Blight on Rice Plant by using Hyperspectral Imaging, Proceedings of the 9th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB), 1-5, 2018.05.
5. Okayasu, T., Nugroho, A.P., Sakai, A., Arita, D., Yoshinaga, T., Taniguchi, R., Horimoto, M., Inoue, E., Hirai, Y., Mitsuoka, M., Affordable Field Environmental Monitoring and Plant Growth Measurement System for Smart Agriculture, 11th International Conference on Sensing Technology (ICST), 10.1109/ICSensT.2017.8304486, 1-4, 2017.12.
6. Andri Prima Nugroho, Takashi Okayasu, Masafumi Horimoto, Daisaku Arita, Takehiko Hoshi, Hidehito Kurosaki, Ken-ichiro Yasuba, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka and Lilik Sutiarso, Development of a field environmental monitoring node with over the air update function, 農業情報研究, 25(3), 86-95, 2016.10.
7. Koichiro Fukami, Toshifumi Mukunoki, Keiko Nakano, Naoki Matsuo, Takashi Okayasu, Water leakage control by using vibratory roller on a dry-seeded rice field in southwestern Japan, Soil and Tillage Research, 166, 138–146, 2016.09.
8. Andri Prima Nugroho, Takashi Okayasu, Rin-ichiro Taniguchi, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka and Lilik Sutiarso, Quantification of 2D Lateral Leaf Motion on Mature Plants Foliage using Optical Flow to Study the Circadian Rhythms, Proceesings of the 2nd International Symposium on Agricultural and Biosystem Engineering, 2016.08.
9. Andri, P. N., Okayasu, T., Hoshi, T., Inoue, E., Hirai, Y., Mitsuoka, aM., Lilik, S., Development of a remote environmental monitoring and control framework for tropical horticulture and verification of its validity under unstable network connection in rural area, Computers and Electronics in Agriculture, 10.1016/j.compag.2016.04.025, 124, 325–339, 2016.06.
10. Andri Prima Nugroho, Takashi Okayasu, Takehiko Hoshi, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, and Lilik, Sutiarso:Development of a remote environmental monitoring and control framework for tropical horticulture and verification of its validity under unstable network connection in rural area, Computers and Electronics in Agriculture, 124, 325–339, 2016.06.
11. Hashimoto, Y., Arita, D., Shimada, A., Yoshinaga, T., Okayasu, T., Uchiyama, H., Taniguchi, R., Measurement and Visualization of Farm Work Information, Proc. CIGR-AgEng conference 2016, 2016.06.
12. Okayasu, T., Tanaka, D., Sakai, A., Sakai, Y., Shimada, K., Awai, K., Inoue, E., Hirai, Y., Mitsuoka, M., Plant growth evaluation for leaf vegetables using simple field monitoring system, Proceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2016, 2016.05.
13. Nugroho, A. P., Okayasu, T., Sakai, A., Inoue, E., Hirai, Y., Mitsuoka, M., Sutiarso, L., Automatic leaf motion analysis using optical flow to diagnose plant behavior in response to environmental changes, roceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2016, 2016.05.
14. Sakai, A., Okayasu, T., Yoshinaga, T., Nugroho, A. P., Arita, D., Inoue, E., Hirai, Y., Mitsuoka, M., Effective investigation of 3D feature value extraction for plant body surface using rgb-d sensor, Proceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2016, 2016.05.
15. Hashimoto, Y., Arita, D., Shimda, A., Okayasu, T., Uchiyama, H., Taniguchi, R., Farmer position estimation in a tomato plant green house with smart devices, Proceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2016, 2016.05.
16. Takashi Okayasu, Takahisa Nakamura, Katsumi Muramoto, Yoshitsugu Momoya, Elastoplastic deformation behavior for ballast under monotonic and cyclic loading conditions, Proceedings of International Conference on International Society for Terrain-Vehicle Systems, 2014.09.
17. Andri Prima Nugroho, Takashi Okayasu, Sribudi Astuti, Muneshi Mitsuoka, Eiji Inoue, Yasumaru Hirai, Lilik Sutiarso, Deployment of agricultural information system – installation and utilization of field monitoring system on agricultural production in Yogyakarta, Indonesia, Proceesings of The International Conference on Sustainable Innovation (ICOSI) 2013, 10.13140/2.1.1643.8401, 2014.06.
18. Takashi Okayasu, Toshihisa Fukuda, Keita Tsuchiya, Koichiro Fukami, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Development of soil tillage simulator using fem-dem quasi-coupling method, Proceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2014, 2014.05.
19. Takashi Okayasu, Daisaku Arita, Andri Prima Nugroho, Takehiko Hoshi, Takashi Yoshinaga, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Effectiveness evaluation on utilization of two snss in japan agriculture, Proceedings of International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2014, 2014.05.
20. Takashi OKAYASU, Andri Prima Nugroho, Daisaku Arita, Akinori Ozaki, Mitsuoka Muneshi, Teruaki NANSEKI, Eiji Inoue, Hirai Yasumaru, Environmental Change Point Analysis and Its Application to Agriculture, Proceedings of International conference on Instrumentation, Control, Information Technology and System Integration, 2013.09, Field environmental information such as air temperature, humidity, and solar radiation would be important not only for evaluation of crop growth progress, status and quality or the occurrence of pests and diseases, but also for optimization of agricultural production processes such as plating, irrigation, fertilization, pest control, and harvesting. However, measured data stored in an agricultural information database, would be vast data with the increase in the number of monitoring devices and sensors installed in such devices. Thus, in order to extract feature values from such vast data, it is necessary to develop some numerical technologies and methods. In this study, the change point analysis based on Singular Spectrum Transformation (SST) was applied for extracting the difference of cultivation environmental conditions in each the tomato greenhouse. The change point scores were detected from the change of CO2 concentration data clearly. They agreed well with the farm work history recorded by a corporative farmer..
21. Andri Prima NUGROHO, Takashi OKAYASU, Mitsuoka Muneshi, Eiji Inoue, Lilik SUTIARSO, Hirai Yasumaru, Development of Web-based Change Point Analysis for Field Environmental Information in Agriculture, Proceedings of International Symposium on Agricultural and Biosystem Engineering 2013, 2013.08.
22. Takahisa FUKUDA, Takashi OKAYASU, Keita TSUCHIYA, Eiji Inoue, Hirai Yasumaru, Mitsuoka Muneshi, Modeling and Prediction of the Mechanical Interaction between Soil and Tillage Tool by DEM, Proc. 11th Int. Conf. Anal. Discontinuous Deformation, 2013.08, Tillage is one of important operations to improve and maintain top soil condition in farmland. The soil condition is different according to soil types and region in general. Various kinds of the tillage methods and tools have been developed up to present. However, their developments have been often conducted by experience and sense using trial and error methods. From these backgrounds, developments of numerical analysis method have been tried to clarify the mechanism for soil-tillage interaction phenomena and to reduce the developing time and costs. In this study, the soil-tillage interaction simulation was established by a three-dimensional geometry of a disk plow and soil layer modeled by using discrete element method (DEM). Trac-tion resistances acting on the disk plow and soil cutting phenomena were estimated in the simulation. They were compared with the experimental results. The simulated results agreed qualitatively with the experimental results..
23. Andri, N.P., Okayasu, T., Inoue, E., Hirai, Y. and Mitsuoka, M., Development of Actuation Framework for Agricultural Informatization Supporting System, Proc. IFAC2013 Bio Robotics Conf., C-16(6 pages), 2013.03.
24. Okayasu, T., Mitsuoka, M., Andri, P.N., Yoshida, H., Nanseki, T. and Inoue, E, Change Point Analysis for Environmental Information in Agriculture, Proc. AFITA/WCCA2012, Seminar20-03(6 pages), 2012.09.
25. Andri, P.N., Okayasu, T., Fushihara, H., Mitsuoka, M. and Inoue, E., Development of Intelligent Control System for Greenhouse, Proc. AFITA/WCCA2012, Seminar16-04(7 pages), 2012.09.
26. Okayasu, T., Yoshida, H., Andri, P.,N., Mitsuoka, M., Inoue, E., Feasibility Study on Informatization Agricultural Supporting System and Evaluation of its Validity, CIGR-AgEng2012, Web(6 pages), 2012.07.
27. Okayasu, T., Morishita, K., Terao, H., Muneshi, M., Inoue, E., Fukami, K., Modeling and prediction of soil cutting behavior by a plow, CIGR-AgEng2012, C2290(6 pages), 2012.07.
28. Okayasu, T., Andri, P.,N., Fushihara, Hirano, O., Yoshida, H., Inoue, E., Development of intelligent irrigation system for greenhouse, Proc. 6th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM(6 pages), 2012.06.
29. Terao, H., Okayasu, T., Fkuda, K. Fukami, K., Mitsuoka, M., Inoue, E., Strength evaluation of bearing in sidedisk for cutting small ditches by finite element method, Proc. 6th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM(6 pages), 2012.06.
30. Okayasu, T. Mitsuoka, M., Andri P.N., Inoue, E., Application of Change Point Analysis for Long-term Environmental Monitoring Data, Proceeding on International Workshop on ICT in Geo-Engineering, 147-153, 2012.05.
31. Okayasu, T., Yoshida, H., Afroja, K., Ozaki, A., Mitsuoka, M., Inoue, E., Development of Simple Field Monitoring System for Agriculture and Evaluation of its Validity, Proc. Int. Conf. Env. Aspects Bangladesh, 205-207, 2011.09.
32. Okayasu, T., Yoshida, H., Miyazaki, T., Nanseki, T., Mitsuoka, M., Inoue, E., Feasibility Study on Field Monitoring and Work Recording System in Agriculture, Proc. ASABE2011, Web, 2011.08.
33. Miyazaki, T., Okayasu, T., Inoue, E., Prediction of compaction behavior of heavy clayey soil beneath an off-road vehicle, Proc. ASABE2011, Web, 2011.08.
34. Okayasu, T., Kamitsuji, N., Murakami, T., Miyazaki, T., Mitsuoka, M., Inoue, E., Fukami, K., Soil Compaction Analysis on Structured Cohesive Soft Ground, Proc. 9th Asia-Pacific Conf. ISTVS, CD-ROM, 2010.09.
35. Miyazaki, T., Okayasu, T., Inoue, E., Tractor Running Tests at Isahaya Bay Reclamation, Proc. 5th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM, 2010.04.
36. Okayasu,T., Yamabe, N., Marui, A., Miyazaki, T., Mitsuoka, M., Inoue, E., Development of Field Monitoring and Work Recording System in Agriculture, Proc. 5th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM, 2010.04.
37. Okayasu, T., Yamabe,N. Mrui, A. Mitsuoka, M., Inoue, E., Development of simple field monitoring system for agricultural production and management, IWABE2009, 320-327, 2009.12.
38. Okayasu, T., Miyazaki, T., Kamitsuji, N., Mitsuoka, M., Inoue, E., Fukami, K., Numerical Soil Compaction Analysis on Structured Soft Ground, ISTRO2009, Izmir, T4-011, 1-8, 2009.06.
39. Yamagata, Y., Okayasu, T., Eguchi, H., Sinkai, S., Furuno, Y., Mitsuoka, M., Inoue, E., Imamura, E., Application of Discrete Element Method to Solve Shaking Separation Mechanisms in Head-Feeding Combine Harvester, Proc. 4th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM, 2008.05.
40. Okayasu, T., Matsuda, H., Furuno, Y., Kamitsuji, N., Mitsuoka, M., Inoue, E., Ueno, M., Fukami, K., Computational Mechanical Consideration on Soil Compaction Behavior due to Wheel Traffics after Tillage, Proc. 4th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), CD-ROM, 2008.05.
41. Okayasu, T., Matsuda, H., Furuno, Y., Mitsuoka, M., Inoue, E., Hashiguchi, K., Elastoplastic deformation analysis on soil compaction by wheel traffics, Plasticity 2008, 373-375, 2008.01.
42. Okayasu, T., Hadano, R., Hirata, M., Yamabe, N., Yasutake, H., Nakaji, K., Mitsuoka, M., Inoue, E., Utilization of Hyperspectral Imaging Technique for Low Protein Rice Production in Kasuya, Fukuoka, Int. S. Agr. Struct. Agr. Engng. 2007, 259-265, 2007.01.
43. Okayasu, T., Matsuda, H., Furuno, Y., Mitsuoka, M., Inoue, E., Hashiguchi, K., Ueno, M., Fukami, K., Elastoplastic finite element analysis on soil compaction phenomena by wheel traffics, Int. WS Agri. Biosy. Engng., 2007.01.
44. Ozaki, S., Hashiguchi, K., Okayasu, T. and Chen, D.H., Finite Element Analysis of Particle Assembly-water Coupled Frictional Contact Problem, CMES, 18, 2, 101-119, 2007.01.
45. Fukami, K., Ueno, M., Hashiguchi, K., Okayasu, T., Mathematical models for soil displacement under a rigid wheel, J. Terramech., 43, 287-301, 2007.01.
46. Okayasu T., Ozaki, T., Hashiguchi, K., Inoue, E., Elastoplastic finite element analysis on uplift problem of ground anchor subject to repeated loading, Proc. 4th Asian-Joint Sympo. Geotech. & Geoenviron. Engng. (JS-Dalian 2006), (in press), 2006.01.
47. Okayasu, T., KInoshita, K., Shimomura, T. Hashiguchi, K., Inoue, E.., Finite element analysis on deformation behavior of metallic body, Proc. 35th Solid Mech. Conf., 165-166, 2006.01.
48. Ozaki, S., Hashiguchi, K., Okayasu, T., Chen, D.H., Finite Element Analysis of the Wheel Traveling Phenomenon by the Subfriction Surface Model, International Conference on Computational & Experimental Engineering and Sciences 2005, 2005.01.
49. Ozaki, S., Hashiguchi, K., Okayasu, T., Chen, D.H., Subfriction Surface Model", International Conference on Computational & Experimental Engineering and Sciences 2005, 1422-1427, 2005.01.
50. Ozaki, T., Hashiguchi, K., Okayasu, T., Elastoplastic finite element analysis of footing problem on soil ground by the subloading surface model, International Conference on Computational & Experimental Engineering and Sciences 2005, 1428-1433, 2005.01.
51. Okayasu, T., Takabayashi, R., Hashiguchi, K., Inoue, E.., Proposal of elasto-viscoplastic constitutive model based on subloading surface concept and its application to metal material, International Conference on Computational & Experimental Engineering and Sciences 2005, 1440-1445, 2005.01.
52. Soil-Water Coupled Finite Element Analysis of Consolidation Test Consdering Frictional Sliding Phenomenon.
53. PIV (Particle Image Velocimetry).
54. Okayasu T., Hashiguchi, K., Yajima, D., Ozaki, T., Ozaki, S., Finite element analysis on uplift problem of ground anchor, Dislocations, Dislocations, Plasticity and Metal Forming (Proc. Plasticity ’05: 11th Int. Symp. Plasticity and its Application), 289-290, 2005.01.
55. Yoshimaru, T., Okayasu T., Hashiguchi, K., Sakajo, S., A basic research of the strength to the solidification soil on the soft ground, Dislocations, Plasticity and Metal Forming (Proc. Plasticity ’05: 12th Int. Symp. Plasticity and its Application), 304-306, 2005.01.
56. Hira, M., Hashiguchi, K., Okayasu, K., Elastoplastic constitutive equation of volcanic sandy soil “SHIRASU” based on the subloading surface model, Dislocations, Plasticity and Metal Forming (Proc. Plasticity ’05: 11th Int. Symp. Plasticity and its Application), 262-264, 2005.01.
57. Elastoplastic finite element analysis on deformation behavior of ground surrounding anchor subjected to cyclic loading.
58. Lowering trap door simulation by finite element method introduced subloading surface model.
59. Deformation of over-consolidated soils under fill construction.
60. An elastoplastic finite element analysis of soil-pile interaction by the subloading-friction model.
61. Finite element analyses of frictional contact problems by the subloading-friction model.
62. Elastoplastic finite element analysis on flow phenomena of powder and granular materials in silo.
63. Studies on the measurement of the soil deformation by piv and the prediction for the stress in soil.
64. Elastoplastic finite element analysis on trap-door problem.
65. Hashiguchi, K., Okayasu, T. and Saitoh, K., Rate-dependent inelastic constitutive equation: The extension of elastoplasticity, Int. J. Plasticity, 20, 463-491, 2004.01.
66. Okayasu, T., Hashiguchi, K., Ozaki, T, Yajima, D., Ozaki, S., Finite element simulation on uplift problem of ground anchor, Proc. Int. Conf. Comput. Exper. Eng. Sci., 806-811, 2004.01.
67. Ozaki, T., Okayasu, T., Hashiguchi, K. Yajima, D., Elastoplastic finite element analysis of the trapdoor problem, Proc. Int. Conf. Comput. Exper. Eng. Sci., 812-817, 2004.01.
68. Yoshimaru, T., Hashiguchi, K., Okayasu T., Sakajo, S., Deformation analysis of cohesive soft grounds with solidified surface under fill construction, Proc. Int. Conf. Comput. Exper. Eng. Sci., 854-859, 2004.01.
69. Friction theory based on the subloading surface concept.
70. Generalized rate-dependent inelastic constitutive equation (Application to metals).
71. Elastoplastic finite element analysis of ground deformation behavior due to uplifting of anchor.
72. Hashiguchi, K., Okayasu, T., Ozaki, T., Extended friction theory based on the subloading surface model, Discolations, Proc. Plasticity ’03: 10th Int. Symp. Plasticity and its Application, 531-533, 2003.01.
73. Setouchi, H., Hashiguchi, K., Shikanai, T., Okayasu, T., Tangential stress-rate effect in soils subjected to cyclic circular stress path in the deviatoric stress plane, Proc. Int. Conf. Comput. Exper. Eng. Sci., 830-835, 2003.01.
74. An advanced technique for displacement measurement of soils.
75. Hashiguchi, K., Saitoh, K., Okayasu, T. and Tsutsumi, S., Evaluation of typical conventional and unconventional plasticity models for prediction of softening behavior of soils, Geotechnique, 52, 561-573, 2002.01.
76. Hira, M., Hashiguchi, K., Okayasu, T. and Miwa, K., Deformation behavior of Shirasu and its prediction by the subloading surface model, Soils and Foundations, 42, 5, 37-46, 2002.01.
77. A proposal for internet education on elastoplasticity.
78. Evaluation of conventional and unconventional plasticity for prediction of softening behavior.
79. Elastoplastic finite element analysis for ground deformation behavior subjected to cyclic loading.
80. Okayasu, T. and Hashiguchi, K., Time-dependent elastoplastic constitutive equation of soils and its application to FEM implementation, Lowland Tech. Int., 3, 2, 66-83, 2001.01.
81. Development of fem program as a soil-water coupled finite deformation introducing the extended subloading surface model.
82. Hashiguchi, K. and Okayasu, T., Time-dependent elastoplastic constitutive equation Based on subloading surface model and its application to soils, Soils and Foundations., 40, 3, 21-36, 2000.01.
83. Hashiguchi K., Saitoh K., Okayasu T., Tsutsumi S., Comparison of Drucker-Prager’s and subloading surface models for prediction of soil deformation behavior, Proc. Int. Symp. Plasticity 2000 (Proc. Eighth Int. Symp. Plasticity and Its Current Applications), 297-299, 2000.01.
84. Okayasu, T., Hashiguchi, K., Tsutsumi, S., Deformation behavior of shallow foundation beneath footing subjected to cyclic load, Proc. Int. Symp. Plasticity 2000 (Proc. Eighth Int. Symp. Plasticity and Its Current Applications), 309-401, 2000.01.
85. Hashiguchi, K., Wu, X., Okayasu, T., Time-dependent constitutive equation of soil, Proc. Int. Symp. Plasticity '99 (Proc. 7th Int. Symp. Plasticity & its Current Appl., 569-572, 1999.01.
86. Image processing on-line measurement for soil displacement.
87. Hashiguchi, K., Wu, X., Okayasu, T. and Tsutsumi, S.,, Time-dependent elastoplastic constitutive model, Metals and Materials, 4, 345-349, 1998.01.
88. Hashiguchi, K., Okayasu, T., Sakajo, S., On the general flow rule, On the general flow rule, Proc. 6th Int. Symp. Numer. Models Geomech., pp.87-92, 1997., 87-92, 1997.01.
89. Ueno, M., Shikanai, T., Okayasu, T., Hashiguchi, K., Nohse, Y., Gotoh, M., Uchiyama, K., Walking motion of the soil reaction on a whee, Proc. 4th Asia-Pacific Regional Conf. Terrain Vechicle Systems, 199-206, 1995.01.
90. Ueno, M., Shikanai, T., Okayasu, T., Hashiguchi, K., Nohse, Y., Gotoh, M, Uchiyama, K., Soil deformation beneath a rigid wheel, Proc. 4th Asia-Pacific Regional Conf. Terrain Vechicle Systems, 133-140, 1995.01.
Works, Software and Database
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9. Internet Teaching Material on the Elastoplasticity (in Japanese).
10. Visual Basic Programming for Beginners on the Web (in Japanese).
Presentations
1. T. Okayasu, D. Arita, T. Yoshinaga, A. Shimada, R. Taniguchi, E. Inoue, Y. Hirai, and M. Mitsuoka, Development of plant phenotyping platform using affordable devices and sensors, AFITA/WCCA2018, 2018.10.
2. Takashi Okayasu, Masami Katayama, Takahisa Nakamura, Ippei Kijiya and Tatsuya Ishikawa, Development of a web-based data sharing and management platform to improve accuracy and reliability of elastoplastic constitutive model, Fourth International Conference on Railway Technology: Research, Development and Maintenance, 2018.09.
3. AminNayeen Al, OkayasuTakashi, InoueEiji , (Kyushu University), HiraiYasumaru (Kyushu University), MitsuokaMuneshi (Kyushu University), HoshiTakehiko (Kindai University), HorimotoMasafumi () Holly & Co. Ltd), Smart irrigation management system to enhance agriculture in Bangladesh using UECS and LPWAN, 第72回農業食料工学会九州支部例会, 2018.08.
4. Astriati Hamidah, Takashi Okayasu, Yu Hoshino, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Andri Prima Nugroho and Lilik Sutiarso, Plant Weight Measurement Using Low Cost Load Cell and Its Accuracy Evaluation, 2019年度農業情報学会年次大会, 2019.05.
5. Nayeen Al Amin, Takashi Okayasu, Masafumi Horimoto, Hideto Kurosaki Takehiko Hoshi, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Development of Irrigation Management System Based on LPWAN-UECS for Distributed Open Fields, 2019年度農業情報学会年次大会, 2019.05.
6. Nayeen Al Amin, Takashi Okayasu, Masafumi Horimoto, Hideto Kurosaki Takehiko Hoshi, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Development of Irrigation Management System Based on LPWAN-UECS for Distributed Open Fields, 2019年度農業情報学会年次大会, 2019.05.
7. Astriati Hamidah, Takashi Okayasu, Yu Hoshino, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Andri Prima Nugroho and Lilik Sutiarso, Plant Weight Measurement Using Low Cost Load Cell and Its Accuracy Evaluation, 2019年度農業情報学会年次大会, 2019.05.
8. 内山美咲・岡安崇史・政井隆之・田中泰洋・前田衡・安武大輔・井上英二・平井康丸・光岡宗司, 深層学習で得られたイチゴ生育特徴量の利用に関する研究, 2019年度農業情報学会年次大会, 2019.05.
9. 長浜義典,野田龍一,野村浩一,安武大輔,岩尾忠重,北野雅治,井上英二,岡安崇史, RGB-D センサを用いた植物生育特徴量の計測とその精度評価, 2019年度農業情報学会年次大会, 2019.05.
10. Nayeen Al Amin, Takashi Okayasu, Masafumi Horimoto, Takehiko Hoshi, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Investigation of communication networking protocol for UECS using IM920 and its validity, 2018年度農業情報学会年次大会, 2018.05.
11. Hideaki Uchiyama, Shunsuke Sakurai, Toshiki Hashimoto and Atsutoshi Hanasaki, Daisaku Arita, Takashi Okayasu, Atsushi Shimada and Rin-ichiro Taniguchi, Sensing Technologies for Advanced Smart Agricultural Systems, International Symposium on Agricultural, Food, Environmental and Life Sciences in Asia, 2017 (AFELiSA 2017), 2017.12.
12. Takashi Okayasu, Andri Prima Nugroho, Atsushige Sakai, Disaku Arita, Takashi Yoshinaga, Rin-ichiro Taniguchi, Masafumi Horimoto, Eiji Inoue, Yasumaru Hirai, and Muneshi Mitsuoka, Affordable Field Environmental Monitoring and Plant Growth Measurement System for Smart Agriculture, International Symposium on Agricultural, Food, Environmental and Life Sciences in Asia, 2017 (AFELiSA 2017), 2017.12.
13. Muhammad Naufal Rauf Ibrahim, Takashi Okayasu, Atsushi Yoshimura, Yoshiyuki Yamagata, Naruto Furuya, Eiji Inoue, Yasumasu Hirai, Muneshi Mitsuoka, Identification and Evaluation of Bacterial Leaf Blight on Rice Field Using Hyperspectral Imaging, International Symposium on Agricultural, Food, Environmental and Life Sciences in Asia, 2017 (AFELiSA 2017), 2017.11.
14. Takashi Okayasu, ICT Application in Agriculture with Affordable Sensors and Devices, 2nd International Conference on Tropical Agriculture, 2017.10.
15. Takashi OKAYASU, IT: an enabling technology for small- and medium-scale farmers in Japan, Conference on Smart Agriculture for Sustainable, Inclusive Productivity, 2017.09.
16. Takashi OKAYASU, Measurement and Visualization of Agricultural Information by Using ICT, Forum “Math-for-Industry” 2016 –Agriculture as a metaphor for creativity in all human endeavor- in QUT, Brisbane, Australia. , 2016.11.
17. Andri Prima Nugroho, Takashi Okayasu, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Lilik Sutiarso, Smart Agriculture Framework and Its Implementation to Open-Field Tropical Horticulture Production, 第70回農業食料工学会九州支部例会, 2016.09.
18. Okayasu, T., Tanaka, D., Sakai, A., Sakai, Y., Shimada, K., Awai, K., Inoue, E., Hirai, Y., Mitsuoka, M., Plant growth evaluation for leaf vegetables using simple field monitoring system, 8th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) , 2016.05.
19. Nugroho, A. P., Okayasu, T., Sakai, A., Inoue, E., Hirai, Y., Mitsuoka, M., Sutiarso, L., Automatic leaf motion analysis using optical flow to diagnose plant behavior in response to environmental changes, 8th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) , 2016.05, We have proposed an automatic leaf motion analysis based on Infrared (IR) photography. The proposed system allows continuous, high-resolution time-lapse imaging, independent of the present of visible light, and based on open source platform. The utilization of microcomputer as a capturing unit might increase the simplicity and flexibility. The IR camera positioned above the plant as top view projection to capture the foliage images. As the motion tracking, the Optical Flow method was adopted, implementing the Lucas-Kanade technique with Shi-Tomasi corner detection. Optical flow is one of the motion detection methods to analyze the motion between two consecutive images by differentiating the constraint. Displacement distance and direction angle were used as a parameter for evaluation with regards to circadian rhythm. As the result, the proposed automatic leaf motion analysis could perform a continuous IR time-lapse photography and analyze the lateral 2D motion using the Optical Flow method. The highest probability of displacement distance observed at 6px (48%) and the direction angle was at 180° (39.2%). According to the visual appearance of time series data, the motion displacement seems to have a regular pattern resembles the circadian rhythm with regards to environmental changes although the noise also appears. To verify the relation between displacement distance, motion angle and circadian rhythm, analysis of phase and amplitude of data using a Fast Fourier Transform Nonlinear Least Squares (FFT-NLS) method will be in our future works..
20. Sakai, A., Okayasu, T., Yoshinaga, T., Nugroho, A. P., Arita, D., Inoue, E., Hirai, Y., Mitsuoka, M., Effective investigation of 3d feature value extraction for plant body surface using rgb-d sensor, 8th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) , 2016.05.
21. Hashimoto, Y., Arita, D., Shimda, A., Okayasu, T., Uchiyama, H., Taniguchi, R., Farmer position estimation in a tomato plant green house with smart devices, 8th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) , 2016.05.
22. Hirai, T., Nakamura, Y., Sakai, A., Okayasu, T., Inoue, E., Mitsuoka, M., Evaluation of a method to estimate light-intercepting characteristics of a rice hill using a RGB-Depth sensor, 8th International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) , 2016.05.
23. Okayasu, T., Trials on ICT application for typical small and medium scale farmers in Japan agriculture, AWSSS2016, 2016.03.
24. OKAYASU, T., Agricultural informatics in Japan -For typical small and medium scale farmers-, THE 11TH INTERNATIONAL WORKSHOP ON NONDESTRUCTIVE QUALITY EVALUATION OF AGRICULTURAL, LIVESTOCK AND FISHERY PRODUCTS, 2015.11.
25. Okayasu, T., Tsuchiya, K., Fukami, K., Inoue, E., Hirai, Y., Mitsuoka, M., Soil tillage simulation using FEM-DEM quasi-coupling method, ISTVS 13th European Conference, 2015.10.
26. Takashi OKAYASU, Takahisa NAKAMURA, Katsumi MURAMOTO, Yoshitsugu MOMOYA, Cyclic elastoplastic deformation analysis on Ballasted railway track, The Second Workshop of Ballasted Track between Japan & the UK Cedar Suite, 2014.10.
27. Daisaku Arita, Takashi Okayasu, Andri Prima Nugroho, Takashi Yoshinaga, Nobushige Doi, Atsushi Shimada, Rin-ichiro Taniguchi, Agricultural information sensing and visualization for farmer-consumer communication, Joint Workshop on Machine Perception and Robotics, 2014.10.
28. Takashi Okayasu, Takahisa Nakamurab, Katsumi Muramoto, Yoshitsugu Momoya, Elastoplastic deformation behavior for ballast under monotonic and cyclic loading conditions, International Conference on International Society for Terrain-Vehicle Systems, 2014.09.
29. Andri Prima Nugroho, Takashi Okayasu, Sribudi Astuti, Muneshi Mitsuoka, Eiji Inoue, Yasumaru Hirai, Lilik Sutiarso, Deployment of agricultural information system – installation and utilization of field monitoring system on agricultural production in Yogyakarta, Indonesia, International Symposium on Innovation Technology for Natural Resource Exploitation Toward Sustainable Environment, 2014.06.
30. Takashi Okayasu, Daisaku Arita, Andri Prima Nugroho, Takehiko Hoshi, Takashi Yoshinaga, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Effectiveness evaluation on utilization of two snss in japan agriculture, International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2014, 2014.05.
31. Takashi Okayasu, Toshihisa Fukuda, Keita Tsuchiya, Koichiro Fukami, Eiji Inoue, Yasumaru Hirai, Muneshi Mitsuoka, Development of soil tillage simulator using fem-dem quasi-coupling method, International Symposium on Machinery and Mechatronics for Agriculture and Biosystems Engineering (ISMAB) 2014, 2014.05.
32. Daisaku Arita, Takashi Okayasu, Andri Prima Nuguroho, Takashi Yoshinaga, Agri-sensing for farmer-consumer communication, Asian Workshop on Smart Sensor Systems, 2014.03.
33. Takashi Okayasu, Utilization of two SNSs in Japan agriculture, 2013 International Symposium on ICT Convergence in the Food and Agriculture, 2013.12.
34. Takashi Okayasu, Atsushige Sakai, Disaku Arita, Takashi Yoshinaga, Rin-ichiro Taniguchi, Eiji Inoue, Yasumaru Hirai, and Muneshi Mitsuoka, Development of Plant Growth Feature Measurement System Using Affordable Devices, International Symposium on Agricultural, Food, Environmental and Life Sciences in Asia, 2017 (AFELiSA 2017), 2013.11.
35. Takashi Okayasu, What is informatization agriculture?, International Symposium on Agricultural, Food, Environmental and Life Sciences in Asia, 2013 (AFELiSA 2013), 2013.11.
36. Takashi OKAYASU, Katsumi MURAMOTO, Takahisa NAKAMURA, Elastoplastic deformation analysis on ballasted track under repeated loading condition, Workshop on Ballasted Track Maintenance between Japan and the United Kingdom, 2013.11.
37. Takashi Okayasu, Andri Prima Nugroho, Daisaku Arita, Akinori Ozaki, Muneshi Mitsuoka, Teruaki Nanseki, Eiji Inoue, Yasumaru Hirai, Environmental Change Point Analysis and Its Application to Agriculture,Proceedings of International conference on Instrumentation, Control, Information Technology and System Integration, 2013.09.
38. Takashi OKAYASU, Informatization Agriculture in Japan, The International Symposium on Agricultural and Biosystem Engineering (ISABE) 2013, 2013.08, Agriculture is dependent on climate, weather, soil conditions, and crop types. Therefore, farmers have tried to develop and improve their own cultivation techniques and senses during the long-term experiences so as to fit the peripheral field environment. Information Communication Technology (ICT) is currently applied in several fields of agriculture to improve the agricultural productivity and cultivation skills. There are many kinds of ICT-agriculture applications that already used for supporting the agricultural production such as environmental monitoring, precision agriculture including spatial data collection, precision irrigation and supplying data to farmers, facility automation including greenhouse control and animal-feeding facility (Wang, 2006).
On the other hand, authors have tried to develop the informatization agricultural supporting system called “Agri-eye” to optimize the agricultural production system (Okayasu et al., 2010). This system is composed of field environmental monitoring and acquisition, crop growth diagnosis and quality evaluation, work history recording, data analysis and visualization, and communication tools, and so on. The field environmental monitoring devices above 50 have been installed in the fields above 10 mainly in the Fukuoka and the Oita prefectures. The work recording system has been also distributed over the Internet and can be utilized through the web browsers on personal computers, mobile phones, and smartphones. The validity of the systems has been verified by the feasibility studies up to present.
In this article, several application examples of the informatization agriculture in Japan will be introduced here..
39. Takahisa FUKUDA, Takashi OKAYASU, Keita TSUCHIYA, Eiji INOUE, Yasumaru HIRAI, Muneshi MITSUOKA, Modeling and Prediction of the Mechanical Interaction between Soil and Tillage Tool by DEM, 11th Int. Conf. Anal. Discontinuous Deformation, 2013.08.
40. Andri Prima NUGROHO, Takashi OKAYASU, Muneshi MITSUOKA, Eiji INOUE, Lilik SUTIARSO, Yasumaru HIRAI, Development of Web-based Change Point Analysis for Field Environmental Information in Agriculture, International Symposium on Agricultural and Biosystem Engineering 2013, 2013.08.
41. Takashi Okayasu, Soil-tool interaction analysis using fem & dem coupling method, International Seminar Program in Chonbuk National University, 2013.05.
42. Andri, N.P., Okayasu, T., Inoue, E., Hirai, Y. and Mitsuoka, M., Development of Actuation Framework for Agricultural Informatization Supporting System, IFAC2013 Bio Robotics Conf., 2013.03.
43. Ozaki, A., Okayasu, T., Rahman, M.A., Choudhury, D.K., Ogata, K., Miyajima, I., Ahmed, A., Ohsugi, T., Inoue, E., Potential of Informatization Agriculture in Bangladesh-Installation and Utilization of Field Monitoring System in Agriculture-, ICEAB2012, 2012.11.
44. Okayasu, T., Utilization of Field Monitoring Information to Agriculture - Potential of Informatization Agriculture in Bangladesh, ICEAB2012, 2012.11.
45. Okayasu, T., Mitsuoka, M., Andri, P.N., Yoshida, H., Nanseki, T. and Inoue, E, Change Point Analysis for Environmental Information in Agriculture, AFITA/WCCA2012, 2012.09.
46. Andri, P.N., Okayasu, T., Fushihara, H., Mitsuoka, M. and Inoue, E., Development of Intelligent Control System for Greenhouse, AFITA/WCCA2012, 2012.09.
47. Andri P,N., Okayasu, T., Mitsuoka, M., Inoue, E., Development of field monitoring and intelligent actuating system in agriculture, 農業機械学会九州支部第66回九州支部例会, 2012.08.
48. Okayasu, T., Yoshida, H., Andri, P.,N., Mitsuoka, M., Inoue, E., Feasibility Study on Informatization Agricultural Supporting System and Evaluation of its Validity, CIGR-AgEng2012, 2012.07.
49. Okayasu, T., Morishita, K., Terao, H., Muneshi, M., Inoue, E., Fukami, K., Modeling and prediction of soil cutting behavior by a plow, CIGR-AgEng2012, 2012.07.
50. Terao, H., Okayasu, T., Fkuda, K. Fukami, K., Mitsuoka, M., Inoue, E., Strength evaluation of bearing in sidedisk for cutting small ditches by finite element method, 6th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), 2012.06.
51. Okayasu, T., Andri, P.,N., Fushihara, Hirano, O., Yoshida, H., Inoue, E., Development of intelligent irrigation system for greenhouse, 6th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), 2012.06.
52. Okayasu, T. Mitsuoka, M., Andri P.N., Inoue, E., Application of Change Point Analysis for Long-term Environmental Monitoring Data, International Workshop on ICT in Geo-Engineering, 2012.05.
53. Soetiarso, L. Goenadi, S., Andri P.N., Okayasu, T., Monitoring of Hydraulic Gradient in Agricultural Land-use using Grid Wireless Sensor Network, International Workshop on ICT in Geo-Engineering, 2012.05.
54. Okayasu, T., Yoshida, H., Miyazaki, T., Nanseki, T., Mitsuoka, M., Inoue, E., Feasibility Study on Field Monitoring and Work Recording System in Agriculture, ASAE2011, 2011.08.
55. Miyazaki, T., Okayasu, T., Inoue, E., Prediction of compaction behavior of heavy clayey soil beneath an off-road vehicle, ASAE2011, 2011.08.
56. Okayasu, T., Kamitsuji, N., Murakami, T., Miyazaki, T., Mitsuoka, M., Inoue, E., Fukami, K., Soil Compaction Analysis on Structured Cohesive Soft Ground, 9th Asia-Pacific Conference of the ISTVS, 2010.09.
57. Okayasu,T., Yamabe, N., Marui, A., Miyazaki, T., Mitsuoka, M., Inoue, E., Development of Field Monitoring and Work Recording System in Agriculture, ISMAB2010, 2010.04.
58. Miyazaki, T., Okayasu, T., Inoue, E., Tractor Running Tests at Isahaya Bay Reclamation, ISMAB2010, 2010.04.
59. Okayasu, T., Yamabe,N. Mrui, A. Mitsuoka, M., Inoue, E., Development of simple field monitoring system for agricultural production and management, IWABE2009, 2009.12.
60. Okayasu, T., Miyazaki, T., Kamitsuji, N., Mitsuoka, M., Inoue, E., Fukami, K., Numerical Soil Compaction Analysis on Structured Soft Ground, ISTRO2009, 2009.06.
61. Fukami, K., Watanabe, T., Tanio, M., Masuda, K., Okayasu, T. Inoue, E., Kamitsuji, N., Ohba, H., Study on Durability Improvement of the Shallow Tillage Seeding Machine with Cutting Small Ditches, ISTRO2009, 2009.06.
62. Okayasu, T., Matsuda, H., Furuno, Y., Kamitsuji, N., Mitsuoka, M., Inoue, E., Ueno, M., Fukami, K., Computational Mechanical Consideration on Soil Compaction Behavior due to Wheel Traffics after Tillage, 4th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), 2008.05.
63. Yamagata, Y., Okayasu, T., Eguchi, H., Sinkai, S., Furuno, Y., Mitsuoka, M., Inoue, E., Imamura, E., Application of Discrete Element Method to Solve Shaking Separation Mechanisms in Head-Feeding Combine Harvester, 4th Int. Symp. Mach. Mech. Agr. Biosys. Engng. (ISMAB), 2008.05.
64. Okayasu, T., Matsuda, H., Furuno, Y., Mitsuoka, M., Inoue, E., Hashiguchi, K., Ueno, M., Fukami, K., Elastoplastic finite element analysis on soil compaction phenomena by wheel traffics, Int. WS Agri. Biosy. Engng., 2007.12.
65. Okayasu, T. Hadano, R., Hirata, M., Yamabe, N., Yasutake, H., Nakaji, K., Mitsuoka, M., Inoue, E., Utilization of Hyperspectral Imaging Technique for Low Protein Rice Production in Kasuya, Fukuoka, Int. S. Agr. Struct. Agr. Engng. 2007, 2007.12.
66. Okayasu, T., Takabayashi, R., Hashiguchi, K., Inoue, E.., Proposal of Elasto-Viscoplastic Constitutive Model based on Subloading Surface Concept and Its Application to Metal Material, International Conference on Computational & Experimental Engineering and Sciences 2005, 2005.12.
67. Ozaki, T., Hashiguchi, K., Okayasu, T., Elastoplastic Finite Element Analysis of Footing Problem on Soil Ground by the Subloading Surface Model, International Conference on Computational & Experimental Engineering and Sciences 2005, 2005.12.
68. Okayasu T., Hashiguchi, K., Yajima, D., Ozaki, T and Ozaki, S., Finite element analysis on uplift problem of ground anchor, Plasticity ’05: 11th Int. Symp. Plasticity and its Application, 2005.01.
69. Hira, M., Hashiguchi, K. and Okayasu, K., Elastoplastic constitutive equation of volcanic sandy soil “SHIRASU” based on the subloading surface model, Plasticity ’05: 11th Int. Symp. Plasticity and its Application, 2005.01.
70. Ozaki, T., Okayasu T., Hashiguchi, K. and Yajima, D., Deformation behavior analysis in tunnel excavation by elastoplastic finite element method based on subloading surface model, Plasticity ’05: 11th Int. Symp. Plasticity and its Application, 2005.01.
71. Yoshimaru, T., Okayasu T., Hashiguchi, K. and Sakajo, S., A basic research of the strength to the solidification soil on the soft ground, Plasticity ’05: 11th Int. Symp. Plasticity and its Application, 2005.01.
72. Yoshimaru, T., Hashiguchi, K. Okayasu, T. and Sakajo, S., Deformation Analysis of Cohesive Soft Ground with Solidified Surface under Fill Construction, International Conference on Computational & Experimental Engineering and Sciences 2004, 2004.09.
73. Okayasu, T., Hashiguchi, K.., Ozaki, T., Yajima, D. and Ozaki, S., Finite Element Simulation on Uplift Problem of Ground Anchor, International Conference on Computational & Experimental Engineering and Sciences 2004, 2004.09.
74. Ozaki,T., Okayasu T., Hashiguchi K. and Yajima D., Elastoplastic Finite Element Analysis of the Trapdoor Problem, International Conference on Computational & Experimental Engineering and Sciences 2004, 2004.09.
75. Setouchi, H. Hashiguchi, K., Okayashu, T. and Shikanai, T., Tangential Stress-rate Effect in Soils Subjected to Cyclic Circular Stress Path in the Deviatoric Stress Plane, International Conference on Computational & Experimental Engineering and Sciences 2004, 2004.09.
76. HASHIGUCHI, K., KHOJASTEHPOUR, M., OKAYASU, T. and OZAKI, S., Symmetric Bifurcation Analysis by the Subloading Surface Model with Tangential Stretching, 第62回農業機械学会年次大会, 2003.04.
77. HASHIGUCHI, K. KHOJASTEHPOUR, M., OKAYASU, T. and OZAKI S.:, Elastoplastic Finite Element Analysis of Soil Beneath a Rigid Wheel, 第61回農業機械学会年次大会, 2002.09.
Membership in Academic Society
  • Japan Forest Engineering Society
  • Japanese Geotechnical Society
  • Japanese Society of Terramechanics
  • Japanese Society of Agricultural Informatics
  • The Japanese Society of Agricultural Machinery and Food Engineers
  • Information Processing Society of Japan
  • The Society of Instrument and Control Engineers
  • Kyushu Branch of The Japanese Society of Agricultural Machinery and Food Engineers
Educational
Educational Activities
Undergraduate school
Agri-Food Production System Engineering
Special Lecture on Advanced Topics of Agriculture
Strength of Materials
Water, Soil and Green in Itoshima Area
Scientific English

Master Course
Advanced Production Systsems Desgin
Bioproduction Environmental Sciences Special Reseach II
Bioproduction Environmental Sciences Project Learning
Bioproduction Environmental Sciences
Advanced Bioproduction Environmental Data Analyses