start-ver=1.4 cd-journal=joma no-vol=61 cd-vols= no-issue=2 article-no= start-page=271 end-page=282 dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=202104 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Reliability-based design for earth-fill dams against severe natural disaster events en-subtitle= kn-subtitle= en-abstract= kn-abstract=The maintenance of geotechnical structures, such as earth-fill dams, is required as a countermeasure against severe natural disasters, particularly earthquakes and heavy rains. The reliability-based analysis introduced here is in response to the recent demand for low-cost improvements.First, a statistical model of N values was determined from Swedish weight sounding (SWS) tests to present the spatial variability of the soil strength. Then, a reliability-based analysis of embankments was conducted by considering the variability of the internal friction angle derived from N value, and the seismic hazard for the Nankai Trough. The next step was to evaluate the probability of the overflow of earth-fills during heavy rains. The rainfall intensity was considered as a probabilistic parameter, and the various rainfall patterns were tested by the proposed method. Finally, the total risk due to both earthquakes and heavy rains was evaluated for an earth-fill site. As a result, the possibility for the practical use of the proposed method in making plans for the maintenance of deteriorated earth-fill dams was verified. en-copyright= kn-copyright= en-aut-name=NishimuraShin-ichi en-aut-sei=Nishimura en-aut-mei=Shin-ichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=ShibataToshifumi en-aut-sei=Shibata en-aut-mei=Toshifumi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=ShukuTakayuki en-aut-sei=Shuku en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= en-keyword=risk evaluation kn-keyword=risk evaluation en-keyword=earth-fill dam kn-keyword=earth-fill dam en-keyword=damage probability kn-keyword=damage probability en-keyword=dam breaching kn-keyword=dam breaching en-keyword=spatial variability kn-keyword=spatial variability en-keyword=spatial variability kn-keyword=spatial variability en-keyword=natural disaster kn-keyword=natural disaster en-keyword=hazard curve kn-keyword=hazard curve en-keyword=fragility curve kn-keyword=fragility curve en-keyword=sounding test kn-keyword=sounding test END start-ver=1.4 cd-journal=joma no-vol=13 cd-vols= no-issue=1 article-no= start-page=8386 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=20230524 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Comprehensive hemocompatibility analysis on the application of diamond-like carbon to ePTFE artificial vascular prosthesis en-subtitle= kn-subtitle= en-abstract= kn-abstract=The aim of this study was to obtain comprehensive data regarding the hemocompatibility of diamond-like carbon (DLC)-coated expanded polytetrafluoroethylene (ePTFE). DLC increased the hydrophilicity and smoothened the surface and fibrillar structure, respectively, of the ePTFE. DLC-coated ePTFE had more albumin and fibrinogen adsorption and less platelet adhesion than uncoated ePTFE. There were scarce red cell attachments in in vitro human and in vivo animal (rat and swine) whole blood contact tests in both DLC-coated and uncoated ePTFE. DLC-coated ePTFE had a similar but marginally thicker band movement than uncoated-ePTFE with SDS-PAGE after human whole blood contact test. In addition, survival studies of aortic graft replacement in rats (1.5 mm graft) and arteriovenous shunt in goats (4 mm graft) were performed to compare the patency and clot formation between DLC-coated and uncoated ePTFE grafts. Comparable patency was observed in both animal models. However, clots were observed in the luminal surface of the patent 1.5 mm DLC-coated ePTFE grafts, but not in that of uncoated ePTFE grafts. In conclusions, hemocompatibility of DLC-coated ePTFE was high and comparable to that of uncoated ePTFE. However, it failed to improve the hemocompatibility of 1.5 mm ePTFE graft probably because increased fibrinogen adsorption canceled the other beneficial effects of DLC. en-copyright= kn-copyright= en-aut-name=GoyamaTakashi en-aut-sei=Goyama en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=FujiiYasuhiro en-aut-sei=Fujii en-aut-mei=Yasuhiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MuraokaGenya en-aut-sei=Muraoka en-aut-mei=Genya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=NakataniTatsuyuki en-aut-sei=Nakatani en-aut-mei=Tatsuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OusakaDaiki en-aut-sei=Ousaka en-aut-mei=Daiki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=ImaiYuichi en-aut-sei=Imai en-aut-mei=Yuichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=KuwadaNoriaki en-aut-sei=Kuwada en-aut-mei=Noriaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=TsujiTatsunori en-aut-sei=Tsuji en-aut-mei=Tatsunori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=ShukuTakayuki en-aut-sei=Shuku en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=UchidaHaruhito A. en-aut-sei=Uchida en-aut-mei=Haruhito A. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=NishiboriMasahiro en-aut-sei=Nishibori en-aut-mei=Masahiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=OozawaSusumu en-aut-sei=Oozawa en-aut-mei=Susumu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=KasaharaShingo en-aut-sei=Kasahara en-aut-mei=Shingo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= affil-num=1 en-affil=Department of Cardiovascular Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=2 en-affil=Department of Cardiovascular Surgery, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=3 en-affil=Department of Cardiovascular Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=4 en-affil=Institute of Frontier Science and Technology, Okayama University of Science kn-affil= affil-num=5 en-affil=Department of Pharmacology, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=6 en-affil=Institute of Frontier Science and Technology, Okayama University of Science kn-affil= affil-num=7 en-affil=Department of Cardiovascular Surgery, Kawasaki Medical Hospital kn-affil= affil-num=8 en-affil=Department of Cardiovascular Surgery, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=9 en-affil=Department of Civil Engineering, Okayama University Graduate School of Environmental and Life Science kn-affil= affil-num=10 en-affil=Department of Chronic Kidney Disease and Cardiovascular Disease, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=11 en-affil=Department of Translational Research and Drug Development, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=12 en-affil=Division of Medical Safety Management, Safety Management Facility, Okayama University Hospital kn-affil= affil-num=13 en-affil=Department of Cardiovascular Surgery, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page=101 end-page=107 dt-received= dt-revised= dt-accepted= dt-pub-year=2014 dt-pub=201406 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Application of the Particle Filter to COHERENS V2 model of Lake Säkylän Pyhäjärvi en-subtitle= kn-subtitle= en-abstract= kn-abstract= en-copyright= kn-copyright= en-aut-name=MANOAkiko en-aut-sei=MANO en-aut-mei=Akiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SHUKUTakayuki en-aut-sei=SHUKU en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil= affil-num=2 en-affil= kn-affil= END start-ver=1.4 cd-journal=joma no-vol=350 cd-vols= no-issue= article-no= start-page=268 end-page=294 dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190615 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=An iterative Bayesian filtering framework for fast and automated calibration of DEM models en-subtitle= kn-subtitle= en-abstract= kn-abstract=The nonlinear, history-dependent macroscopic behavior of a granular material is rooted in the micromechanics between constituent particles and irreversible, plastic deformations reflected by changes in the microstructure. The discrete element method (DEM) can predict the evolution of the microstructure resulting from interparticle interactions. However, micromechanical parameters at contact and particle levels are generally unknown because of the diversity of granular materials with respect to their surfaces, shapes, disorder and anisotropy. The proposed iterative Bayesian filter consists in recursively updating the posterior distribution of model parameters and iterating the process with new samples drawn from a proposal density in highly probable parameter spaces. Over iterations the proposal density is progressively localized near the posterior modes, which allows automated zooming towards optimal solutions. The Dirichlet process Gaussian mixture is trained with sparse and high dimensional data from the previous iteration to update the proposal density. As an example, the probability distribution of the micromechanical parameters is estimated, conditioning on the experimentally measured stress–strain behavior of a granular assembly. Four micromechanical parameters, i.e., contact-level Young’s modulus, interparticle friction, rolling stiffness and rolling friction, are chosen as strongly relevant for the macroscopic behavior. The a priori particle configuration is obtained from 3D X-ray computed tomography images. The a posteriori expectation of each micromechanical parameter converges within four iterations, leading to an excellent agreement between the experimental data and the numerical predictions. As new result, the proposed framework provides a deeper understanding of the correlations among micromechanical parameters and between the micro- and macro-parameters/quantities of interest, including their uncertainties. Therefore, the iterative Bayesian filtering framework has a great potential for quantifying parameter uncertainties and their propagation across various scales in granular materials. en-copyright= kn-copyright= en-aut-name=ChengHongyang en-aut-sei=Cheng en-aut-mei=Hongyang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=ShukuTakayuki en-aut-sei=Shuku en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=ThoeniKlaus en-aut-sei=Thoeni en-aut-mei=Klaus kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=TemponePamela en-aut-sei=Tempone en-aut-mei=Pamela kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=LudingStefan en-aut-sei=Luding en-aut-mei=Stefan kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=MagnanimoVanessa en-aut-sei=Magnanimo en-aut-mei=Vanessa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Multi-Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente kn-affil= affil-num=2 en-affil=Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Centre for Geotechnical Science and Engineering, The University of Newcastle kn-affil= affil-num=4 en-affil=Division of Exploration and Production kn-affil= affil-num=5 en-affil=Multi-Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente kn-affil= affil-num=6 en-affil=Multi-Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente kn-affil= en-keyword=Iterative parameter estimation kn-keyword=Iterative parameter estimation en-keyword=Sequential Monte Carlo kn-keyword=Sequential Monte Carlo en-keyword=Dirichlet process mixture model kn-keyword=Dirichlet process mixture model en-keyword=Discrete element method kn-keyword=Discrete element method en-keyword=X-ray tomography kn-keyword=X-ray tomography en-keyword=Cyclic oedometric compression kn-keyword=Cyclic oedometric compression END start-ver=1.4 cd-journal=joma no-vol=25 cd-vols= no-issue=1 article-no= start-page=1 end-page=4 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=202003 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Efficient modelling of 3-d finite element mesh formation with use of 3-d topographic survey kn-title=3次元計測を利用した効率的な3次元有限要素モデル化法の提案 en-subtitle= kn-subtitle= en-abstract= kn-abstract= In this decade, 3-dimensional topographic survey has been developed by using the UAV as like drones. With the technique, the complete topographies of the geo-structures can be measured. Although the accurate shapes of the geo-structures can be obtained, the numerical methods as like the finite element method is are not related to the 3-dimensional survey directly. In this research, the finite mesh modelling technique with use of the 3-D topographic survey is developed. The models of the earth-fill embankments formed from measured 3-D data are introduced as the examples. en-copyright= kn-copyright= en-aut-name=KANESHIGEMinoru en-aut-sei=KANESHIGE en-aut-mei=Minoru kn-aut-name=金重稔 kn-aut-sei=金重 kn-aut-mei=稔 aut-affil-num=1 ORCID= en-aut-name=NISHIMURAShin-ichi en-aut-sei=NISHIMURA en-aut-mei=Shin-ichi kn-aut-name=西村伸一 kn-aut-sei=西村 kn-aut-mei=伸一 aut-affil-num=2 ORCID= en-aut-name=SHIBATAToshifumi en-aut-sei=SHIBATA en-aut-mei=Toshifumi kn-aut-name=柴田俊文 kn-aut-sei=柴田 kn-aut-mei=俊文 aut-affil-num=3 ORCID= en-aut-name=SHUKUTakayuki en-aut-sei=SHUKU en-aut-mei=Takayuki kn-aut-name=珠玖隆行 kn-aut-sei=珠玖 kn-aut-mei=隆行 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=岡山大学大学院環境生命科学研究科 affil-num=2 en-affil= kn-affil=岡山大学大学院環境生命科学研究科 affil-num=3 en-affil= kn-affil=岡山大学大学院環境生命科学研究科 affil-num=4 en-affil= kn-affil=岡山大学大学院環境生命科学研究科 en-keyword=3-dimensional survey kn-keyword=3-dimensional survey en-keyword=UAV kn-keyword=UAV en-keyword=finite element mesh modelling kn-keyword=finite element mesh modelling END