Authorship：Lead author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)   Publisher：Japan Synchrotron Radiation Research Institute  

DOI： 10.18957/rr.10.4.336

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Ceramic Society of Japan  

<p>Deposition condition of (001)-epitaxial K(Ta_0.6Nb_0.4)O₃ (KTN) films on SrRuO₃/SrTiO₃ substrates by pulsed laser deposition was optimized. The optimized KTN film showed a saturated ferroelectric hysteresis loop with large withstand electric field, and the paraelectric to ferroelectric phase transition at room temperature (RT). Electro-optic (EO) property was characterized by modulation ellipsometry at RT, showing the maximum EO coefficient <i>r</i>_c of 42 pm/V, which is larger than the previously reported value for KTN thin films having the same composition. Our findings show the importance of the precise tuning of deposition condition to achieve the large EO response in KTN films, promoting the potential application as a light modulator in EO devices at ambient temperature in the future.</p>

DOI： 10.2109/jcersj2.21187

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CiNii Research

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-022-12990-z

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/5.0056121

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/5.0023937

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Ceramic Society of Japan  

<p>Artificial superlattice thin films of (Pb_0.9Sr_0.1)TiO₃ (PST)<i>_n</i>/SrTiO₃ (STO)<i>_m</i> were grown on SrRuO₃-electroded DyScO₃ (001)_pc substrates by pulsed laser deposition. X-ray diffraction (XRD) showed that the fabricated superlattice thin films have a good periodicity in the out-of-plane direction, indicating the sharp interfaces regardless of the difference in layer thickness. Synchrotron XRD indicated that the film with <i>n</i>/<i>m</i> = 14/20 had a weak periodicity in the in-plane direction, which may had arisen from the ordered polar vortex arrays existing in the PST layers. All the fabricated superlattice thin films showed the electric field-induced strain, though its magnitude was smaller than that for typical ferroelectric materials.</p>

DOI： 10.2109/jcersj2.20022

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CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/5.0012998

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Language：Japanese   Publisher：The Japan Society of Applied Physics  

DOI： 10.11470/jsapmeeting.2020.1.0_1232

CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.5117218

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Ceramic Society of Japan  

<p>The influence of compressive strain on the linear electro-optic (EO) effect in <i>c</i>-domain (Ba<i>_x</i>Sr₁₋<i>_x</i>)TiO₃ (BST) thin films was theoretically investigated using a phenomenological thermodynamic model. We considered that the <i>c</i>-domain BST thin films were grown on cubic substrates and an electric field was applied parallel to the direction of spontaneous polarization. To estimate the EO coefficients, we considered not only the intrinsic EO effect but also the elasto-optic effect by converse piezoelectric response. We found that the EO response is mostly determined by the difference in temperature from the ferroelectric-to-paraelectric phase transition boundary modified by the strain, and the elasto-optic effect appreciably affects the overall EO coefficient when the intrinsic EO effect is weak.</p>

DOI： 10.2109/jcersj2.19011

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CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/15361055.2019.1658039

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.18494/SAM.2019.2149

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/c8cp04839h

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.7567/JJAP.57.0902B1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Ceramic Society of Japan  

Self-assembled Pb(Zr,Ti)O₃ (PZT) nanorods were grown by pulsed laser deposition (PLD) at an elevated oxygen pressure. PZT grew as a film in the initial growth stage and formed nanorods upon further deposition. The influence of the substrate temperature, target-substrate distance, and Pb composition of the targets on nanorod growth was investigated. It was found that the average radius of the PZT nanorods was larger at higher substrate temperatures and longer target-substrate distances, which can be explained respectively by the enhanced surface diffusion and shadowing effect of the PLD species. The results of this study can contribute to controlling the sizes of PZT nanorods to tune their piezoelectric response.

DOI： 10.2109/jcersj2.17255

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CiNii Research

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.5025778

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.nimb.2017.12.023

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jssc.2017.10.003

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.7567/JJAP.56.10PF15

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-017-05475-x

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.intermet.2017.02.020

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Ceramic Society of Japan  

Positive-up-negative-down (PUND) polarization measurement was employed to indirectly estimate the electrocaloric (EC) effect in ferroelectric films. By subtracting the conductive component from the observed charge profile, the polarization values at various electric fields and temperatures were precisely determined. The estimated EC effect for an epitaxial Ba_0.3Sr_0.7O₃ thin film fabricated on SrRuO₃/SrTiO₃ (001) substrate showed the largest temperature change at around the ferroelectric-paraelectric phase transition temperature, which agrees with the theoretical prediction. On the other hand, the EC effect estimated by the conventional hysteresis loop measurement showed different peaking temperature from the theoretical prediction. The deviation became larger with lowering the measurement frequency. The observed results indicate the importance of precise evaluation of polarization for the examined temperature-electric field space.

DOI： 10.2109/jcersj2.16283

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CiNii Research

Language：English   Publishing type：Research paper (scientific journal)  

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DOI： 10.7567/JJAP.52.09KA09

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2109/jcersj2.121.690

Language：Japanese  

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Language：English   Publishing type：Research paper (bulletin of university, research institution)  

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)  

Language：English   Publishing type：Research paper (bulletin of university, research institution)  

Authorship：Lead author   Language：English  

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The electrical conductivity (sigma), Seebeck coefficient (S), and power factor (sigma S-2) of perovskite-type LaFeO3, La1-xSrxFeO3 [0.1 <= x <= 0.4] and LaFe1-yNiyO3 [0.1 <= y <= 0.6] were investigated in the temperature range of 300-1100 K to explore their possibility as thermoelectric materials. The electrical conductivity of LaFeO3 showed semiconducting behavior, and its Seebeck coefficient changed from positive to negative around 650 K with increasing temperature. The electrical conductivity of LaFeO3 increased with the substitutions of Sr and Ni atoms, while its Seebeck coefficient decreased. The Seebeck coefficient of La1-xSrxFeO3 was positive, whereas that of LaFe1-yNiyO3 changed from positive to negative with increasing Ni content. The substitutions of Sr and Ni were effective in increasing the power factor of LaFeO3; 0.0053 x 10(-4) Wm(-1) K-2 for LaFeO3 (1050K), 1.1 x 10(-4) Wm(-1) K-2 for La1-xSrxFeO3 (x = 0.1 at 1100K) and 0.63 x 10(-4) Wm(-1) K-2 for LaFe1-yNiyO3 (y = 0.1 at 1100K).

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Authorship：Lead author   Language：English  

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Rod-like single crystals of Sr6Co5O14.3 Were grown by the flux method, and the electrical conductivity (sigma), Seebeck coefficient (S) and power factor (sigma S-2) were investigated in the temperature range of 300-900 K in air to explore the potential as thermoelectric materials. Sr6Co5O14.3 is an oxygen-nonstoichiometric phase of Sr6Co5O15, which is a member of the homologous (A(3)Co(2)O(6))(m)(A(3)Co(3)O(9))(n) [A = Ca, Sr, Ba] series including Ca3Co2O6 (m = 1, n = 0) and BaCoO3 (m = 0, n = 1) as the end members. The rod-like single crystals mainly grew along Co-O one-dimensional chains (c-axis) consisting of face-sharing CoO6 octahedra and CoO6 triangular prisms. The electrical conductivity along the Co-O chains showed semiconducting behavior (260-9600 S m(-1) in the temperature range of 300-900 K). The Seebeck coefficient was positive, and decreased with increasing temperature (280-140 mu V K-1). The power factor increased with increasing temperature (0.20 x 10(-4)-1.9 x 10(-4) W m(-1) K-2), which was about one order of magnitude larger than that of polycrystalline Sr6Co5O15.

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This paper describes a neutron diffraction study that has located hydrogen atoms in a proton-conducting perovskite oxide more definitely than ever. The neutron diffraction data were collected on BaSn0.5In0.5O2.75 with and without dissolved D2O at 10 K. Data analysis by the Rietveld method and the maximum entropy method revealed that deuterium atoms were located at or very close to the 12h site of the cubic perovskite structure (space group Pm3m) with an O-D distance of 1.0 angstrom. This hydrogen position is similar to those suggested by the previous computational studies for proton-conducting perovskite oxides. (c) 2006 Elsevier B.V All rights reserved.

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High-resolution, powder, neutron diffraction data have been collected on the protonic conductors SrZr0.95Sc0.05O3-alpha with and without dissolved heavy water at a temperature of 10K. Diffraction data have been analyzed by the Rietveld and maximum entropy methods (MEM). The crystal structure of these samples at 10K is successfully refined assuming a perovskite-type structure with the space group Pnma. The deuterons are located outside the ZrO6/ScO6 octahedra near oxygen atoms. (c) 2006 Elsevier B.V. All rights reserved.

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Language：English   Publishing type：Research paper (scientific journal)  

The local geometry around hydrogen and activation energies for hydrogen transfer in undoped, Y-and Al-doped SrZO(4), have been studied using the density functional theory under the generalized gradient approximation. It is shown that strong, O-H bond is formed and orientated towards the outside of the ZrO6 octahedron in SrZrO3. The hydrogen tends to approach the dopant ion in the doped oxides. It is found that large local distortion is induced around hydrogen and dopant ion, and affects the activation energy of hydrogen transfer largely. The calculated activation energies are in agreement with the experimental values in the doped oxides.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Local electronic states around hydrogen and acceptor ions in SrZrO3 are simulated by the DV-X alpha molecular orbital method to examine their effects on protonic conductivity. The calculated ioncities of the acceptor dopant ion, M. and the surrounding six oxygen ions, O-(i) (i = 1-6) are found to change largely with M in the doped oxide, where M's are Yb, Y, In, Al and Ga. There is a clear tendency that the protonic conductivity decreases as these ionocities around the dopant ion. M, deviate further from the ones around the Zr ion in un-doped oxide. Also, in a geometrical viewpoint, the bond order between M and O-(i) (i = 1-6) ions is another indication to control the protonic conductivity. The presence of the slightly weaker M-O-(i) bond than the Zr-O bond causes small expansion of the MO6 octahedron, and then gives a nearly symmetrical position for proton to move readily to the neighboring oxygen sites. These results are also found in the other oxides, BaZrO3 and CaZrO3. Both the ionicity and the bond order are indeed useful parameters for the design of perovskite-type oxides with high protonic conductivity.

Authorship：Lead author   Language：English  

The most stable crystal structures of complex hydrides, MXHn (NaAlH4, LiAlH4, LiBH4 and LiNH2) were simulated by the plane-wave pseudopotential method. The local chemical bonds between constituent ions were simulated using the DV-X alpha molecular orbital method. As a result, it was found that the covalent interaction is operating between X and H ions to form a XHn ion in MXHn. In addition, the ionic interaction is operating between M and XHn ions through the charge transfer from M to XHn ions. On the basis of this understanding of the nature of the chemical bond between ions, a phase stability diagram of complex hydrides was proposed using two parameters. One is the bond energy of XH diatomic molecules and the other is electronegativity difference, Delta Phi(X-M), between M and X ions. The calculated stability change by doping into NaAlH4 could by explained qualitatively following this diagram. This diagram will provide us a clue to the modification of hydrides to lower the hydrogen decomposition temperature.

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Proton concentration in SrZr0.95M0.05O3-alpha (M=Ga, Sc, Y and Nd) was measured with a thermobalance at different temperatures (T=673-973 K) and water vapor pressures (P-H2O=0.9-12.8 kPa). At all the pressures and temperatures examined, the amount of proton concentration in these samples is in the order of Sc>Y>Ga>Nd. By an equilibrium evaluation, we estimated the maximum possible proton concentration about 2.0 mol% in these samples. Infrared (IR) absorption spectra are measured in these samples. The absorption bands can be fitted by four (M=Ga, Y, Nd) or three (M=Sc) Gaussian bands.

Language：English   Publishing type：Research paper (scientific journal)  

Nitrogen doping into an erbium (Er)-containing ZnO specimen through the N+ irradiation and the subsequent annealing in air was found to increase the photoluminescence (PL) intensity around 1.54 mum by about 40 times. The existence of nitrogen in the specimen was proved firmly by means of the N-14(d,alpha)C-12 nuclear reaction analysis. Further, the Ne+ irradiation was conducted instead of the N+ irradiation, but no effect was observed in the PL spectra. So, it was concluded that the substitution of N for O could modify the local structure around Er3+, resulting in the surprisingly large enhancement of the PL intensity. (C) 2005 American Institute of Physics.

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The first-principles calculations based on the density functional theory were carried out to investigate the effects of A-cations on the protonic conductivity of AZrO(3) (A=Ca, Sr, Ba). The local geometries around proton and dopant ion, formation energies of interstitial proton and activation energies for proton transfer were simulated in the In-doped CaZrO3, SrZrO3 and BaZrO3. The results showed that the crystallographic feature of AZrO(3) (A=Ca, Sr, Ba) is an important factor to control the protonic conduction. In the In-doped CaZrO3 or SrZrO3 with the orthorhombic structure, there is a unique stabilized proton site located between two adjacent octahedra. But in the In-doped BaZrO3 with the cubic structure, there exists a certain region of stable sites between them. As the ionic radii of A-cations decrease, the crystal symmetry changes from cubic to orthorhombic, resulting in the rotation of ZrO6 (or InO6) octahedra, which causes the increase of activation energies for proton transfer in the oxides.

Language：English   Publishing type：Research paper (scientific journal)  

The Er-containing ZnO specimens were treated through the N+ irradiation and the subsequent annealing, and the effect was investigated on the photoluminescence (PL) spectra around 1.54 mum. When the specimens were annealed at 1273 K in air after the N+ irradiation, the PL spectra changed remarkably. The PL intensity increased by about 35 times after the N+ irradiation and the subsequent annealing, and there was the attendant shift in the wavelength of the strongest peak from 1.534 to 1.539 mum. Thus, the N+ irradiation and the subsequent annealing could modify the local structure around Er3+ ions in ZnO, resulting in the surprisingly large enhancement of the PL intensity.

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The effects of dopants on the electrical conductivity of ZnO were investigated through the ac impedance spectroscopy. The doping of Al increased the electrical conductivity of ZnO greatly, whereas the doping of Li decreased it both in the grain and in the grain boundary. The doping of the 3d transition metals (Co, Mn, and Cu) made the grain boundary more resistive, but the doping effect on the electrical conductivity inside the grain was varied depending on the doping elements. The doping of Co had no significant effects on the electrical conductivity of the grain, and the doping of Mn made the grain a little more resistive. The doping of Cu made the grain much more resistive. In addition, hydrogen was introduced into ZnO by the ion implantation method. The electrical conductivity in the hydrogen-implanted ZnO layer increased by four orders of magnitude. The mechanisms for the doping effects were discussed in this investigation.

Language：English   Publishing type：Research paper (scientific journal)  

Hydrogen ion implantation technique was applied to introduce hydrogen into ZnO. ZnO specimens with different electrical conductivity were prepared by the addition of some dopants. The elastic recoil detection analysis was used to measure the content of hydrogen in ZnO before and after the hydrogen ion implantation. The electrical conductivity of ZnO was increased greatly by the hydrogen ion implantation. The increase of the electrical conductivity varied with the dopants. The greatest increase was about 9 orders of magnitude in the highly resistive Cu-doped ZnO. The mechanism for such a hydrogen effect was discussed. (C) 2003 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.

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Formation energies of various defects in Al2O3 and SiO2 are calculated by using the plane-wave pseudopotential method. Also, the formation energies of Schottky defects and Frenkel defects are evaluated on the basis of these calculations. It is shown that formation energies of these defects are higher in SiO2 than in Al2O3. In other words, less defects are formed in SiO2 than in Al2O3. It is also found that the principal defect is the cation Frenkel defect in Al2O3 but the anion Frenkel defect in SiO2. These results agree with the experimental results that Al ions diffuse preferably in Al2O3 but oxygen ions diffuse in SiO2 at high temperatures.

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The electron density distributions in a series of metal oxides are calculated using the DV-Xalpha molecular orbital method. It is found that the logarithm of the electron density, logrho(r), decreases with the distance, r, from the oxygen nucleus, while keeping a constant slope relevant to oxygen atom. The magnitude of the slope is about 15.75 for O-1s electrons, and about 6.61 for O-2s, 2p electrons being nearly close to the respective values of 16 and 8, expected from the radial distribution functions of hydrogen-like atom containing only one electron. The extent of the region for the O-2s, 2p electrons changes with metal species in the oxides, but the slope remains unchanged. Furthermore, it is shown that the nature of the chemical bonding is well represented in 109 (rho(min)Z(-3)) VS. 2(Z/n) r(min) in plots, where rho(min) is the minimum electron density, r(min) is the distance r at rho(min), Z is the atomic number, and n is the principal quantum number.

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The local electronic structures are simulated for a perovskite-type oxide with four polymorphous phases, SrZrO3, using the DV-Xalpha molecular orbital method. It is found that a series of phase transitions occurs at certain temperatures so as to retain not only the Zr-O bond strength, but also the Sr-O bond strength, by the tilting of ZrO6 octahedra and the attendant accommodation to the Zr-O and the Sr-O interionic distances. The occurrence of such smart phase transitions is observed in other perovskite-type oxides, SrRuO3 and SrHfO3. Another type of phase transition occurs by the cooperative ionic displacements along the [100] direction in BaTiO3. The differences in the local chemical bond are discussed between the two types of phase transitions.

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The photoluminescence (PL) around the wavelength of 1.54 mum from the Er-containing ZnO specimens was measured at room temperature by the indirect excitation of the He-Cd laser (325 nm). The PL intensity varied greatly with the Er concentration and the specimen preparation conditions as well. The specimens with the Er content of about 2.6 at%, sintered at 1623 K, and cooled quickly to room temperature in air showed the highest PL intensity at 1.534 mum. The local structure of the optically active Er centers in ZnO was also discussed, and the appropriate optically active center might be the Er ions existing in the grain boundaries.

Language：English   Publishing type：Research paper (scientific journal)  

A universal relation between electron density minima and ionic radii, was discovered from the first principles calculations of electronic structures in ceramics over 60 species, including oxides, borides, carbides, nitride and fluorides. Every ceramic falls on a curve Of log(rho(min)Z(-3)) vs. 2(Z/n)r(min), where rho(min) is the minimum electron density in the line linking the first-nearest-neighbor nuclei, r(min) is the distance r at rho(min) is the atomic number, and n is the principal quantum number.

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The doping effects of Cu on the electrical conductivity of ZnO were studied in the simple binary system through the ac impedance spectroscopy. The Cu doping decreased the electrical conductivity of ZnO by several orders of magnitude. The Cu doping decreased the electrical conductivity of ZnO both in the grain and in the grain boundary. Hydrogen was introduced into the Cu-doped ZnO specimens by the ion implantation technique. The electrical conductivity of the hydrogen-implanted layer increased by about 9 orders of magnitude at most. The mechanism for such a hydrogen effect was also discussed.

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Language：English   Publishing type：Research paper (scientific journal)  

The local geometry and chemical bonding around proton and acceptor dopant in perovskite-type oxide SrZrO3 have been investigated by the pseudopotential method and the DV-Xalpha molecular orbital method. Special attention is directed towards the MO6 octahedron in the perovskite-type structure, where Ms are acceptor dopants (e.g., Y and Al) substituted for Zr ions in the oxide. <BR>It is shown that local electronic state of the constituent ions in the MO6 octahedron is a good measure of the local geometrical change of the octahedron with doping. For example, there is a strong resemblance in the local ionic state and hence the local geometry of the octahedron between the undoped and Y-doped oxides. However, there is little resemblance between the undoped and Al-doped oxides. The calculated activation energy for protonic conduction is higher in the Al-doped oxide than that in the Y-doped oxide, in agreement with experimental results. From these results, it is found that such an acceptor dopant that does not change local electronic state or local geometry of the octahedron is a preferable element for enhancing protonic conductivity in perovskite-type oxides.

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The optimized geometries and formation energies of hydrogen in the perovskite-type oxide, SrZrO3, have been calculated using the density functional theory under the generalized gradient approximation (GGA). The stable hydrogen sites in the oxide are examined with special interests. It is shown that the hydrogen is tightly bound to an oxygen ion and located slightly outside the ZrO6 octahedron in SrZrO3. The O-H bond orientates towards the second-nearest-neighbor oxygen ion, which induces large local displacements of adjacent oxygen ions. For example, the nearest-neighbor oxygen ions tend to approach the hydrogen. The addition of an acceptor dopant, yttrium, modifies such local distortion of oxygen ions around the hydrogen as to increase protonic conductivity. In addition, the calculated hydrogen formation energy shows that the hydrogen behaves as a shallow donor in SrZrO3. The fundamental principles of doping and atmosphere control in proton conducting oxides are also given in view of energetics.

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Local electronic structures around hydrogen and acceptor ions in SrZrO3 are simulated by the DV-X alpha molecular orbital method. In pure SrZrO3, there is a band gap of about 6 eV between the O-2p valence band and the Zr-4d conduction band, in agreement with experiments. When Y or Sc is doped into SrZrO3, an acceptor level appears just above the valence band. When hydrogen is introduced into SrZrO3, a donor level appears below the conduction band. Also, an oxygen ion vacancy makes the defect level below the conduction band. It is shown that charge compensation takes place among these acceptor, donor and defect levels. In addition, local electronic structure around hydrogen is found to change largely with the acceptor dopants, Sc and Y. For example, the metal-oxygen bond strength changes in the order, Y-O < Zr-O < Sc-O, which probably modifies the thermal vibrational amplitude of oxygen ions near hydrogen, and affects protonic conductivity in the doped SrZrO3.

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The electronic structures of small octahedral model clusters containing hydrogen, 3d, 4d, 5d transition and non-transition elements are investigated by the DV-X alpha molecular orbital method. It is found that hydrogen makes a strong chemical bond with the hydride non-forming elements, B, as long as the hydride forming elements, A, exist in the neighborhood. This is a reason why hydrogen is located preferentially near the hydride non-forming elements in many hydrides. Also it is suggested that the ratio of the A-B bond strength to the A-A bond strength lies in a certain range for conventional hydrogen storage A-B alloys. (C) 1999 Elsevier Science S.A. All rights reserved.

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Event date： 2023.11

Presentation type：Oral presentation (general)  

Event date： 2023.10

Presentation type：Poster presentation  

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Venue：Charleston, USA  

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Venue：東京工業大学すずかけ台キャンパス  

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Event date： 2022.9

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Venue：東北大学  

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Venue：徳島大学  

Event date： 2022.9

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Venue：Kofu, Japan  

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Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学札幌キャンパス -> オンライン  

Event date： 2020.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Keystone, USA -> Virtual  

Event date： 2020.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市, ホテルコープイン京都  

Event date： 2020.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市, ホテルコープイン京都  

Event date： 2019.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名城大学   Country：Japan  

Event date： 2019.8

Language：English   Presentation type：Poster presentation  

Venue：ASTANA, KAZAKHSTAN   Country：Kazakhstan  

Event date： 2019.6

Language：English   Presentation type：Oral presentation (general)  

Country：France  

Event date： 2015.11

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋大学   Country：Japan  

Event date： 2015.11

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学   Country：Japan  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋国際会議場   Country：Japan  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：富山大学   Country：Japan  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：ホテルコープイン京都   Country：Japan  

Event date： 2015.3

Language：Japanese   Presentation type：Poster presentation  

Venue：岡山大学   Country：Japan  

Event date： 2015.2

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：機械振興会館   Country：Japan  

Event date： 2014.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋工業大学   Country：Japan  

Event date： 2014.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2014.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋工業大学   Country：Japan  

Event date： 2014.11

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2014.10

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京電機大学   Country：Japan  

Event date： 2014.9

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学   Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Poster presentation  

Venue：鹿児島大学   Country：Japan  

Event date： 2014.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2014.7

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2014.6

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市   Country：Japan  

Event date： 2014.3

Language：Japanese   Presentation type：Poster presentation  

Venue：慶応大学   Country：Japan  

Event date： 2014.1

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋市   Country：Japan  

Event date： 2014.1

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋市   Country：Japan  

Event date： 2014.1

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋市   Country：Japan  

Event date： 2013.12

Language：English   Presentation type：Oral presentation (general)  

Country：United States  

Event date： 2013.12

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2013.10

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学   Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学   Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：金沢大学   Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：信州大学   Country：Japan  

Event date： 2013.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：龍谷大学   Country：Japan  

Event date： 2013.6

Language：English   Presentation type：Oral presentation (general)  

Country：Czech Republic  

Event date： 2013.6

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都   Country：Japan  

Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市   Country：Japan  

Event date： 2013.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神奈川工科大学   Country：Japan  

Event date： 2013.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京工業大学   Country：Japan  

Event date： 2012.12

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2012.11

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：名古屋工業大学   Country：Japan  

Event date： 2012.10

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：愛媛大学城北地区、松山大学文京キャンパス   Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：愛媛大学，松山大学   Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：愛媛大学   Country：Japan  

Event date： 2012.8

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2012.7

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2012.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：横浜国立大学常盤台キャンパス   Country：Japan  

Event date： 2010.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：豊橋技術科学大学   Country：Japan  

Event date： 2010.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2009.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2008.6

Language：English   Presentation type：Oral presentation (general)  

Event date： 2008.4

Language：English  

Country：Japan  

Event date： 2008.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2008.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2008.1

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2008.1

Language：English   Presentation type：Oral presentation (general)  

Event date： 2007.11

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2007.11

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2007.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.7

Language：English   Presentation type：Poster presentation  

Event date： 2007.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2007.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.10

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2006.10

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2006.9

Language：English   Presentation type：Poster presentation  

Event date： 2006.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.8

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2006.7

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2005.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2005.9

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2005.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2005.8

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2005.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2005.7

Language：English   Presentation type：Poster presentation  

Event date： 2005.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.9

Language：English   Presentation type：Poster presentation  

Event date： 2004.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2004.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.11

Language：English   Presentation type：Poster presentation  

Event date： 2003.11

Language：English   Presentation type：Poster presentation  

Event date： 2003.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.3

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2003.3

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2003.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2003.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2002.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2002.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2002.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2002.8

Language：English   Presentation type：Oral presentation (general)  

Event date： 2002.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2002.7

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2002.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2001.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2001.7

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2001.7

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2001.7

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2001.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2001.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2000.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2000.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2000.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2000.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1999.12

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 1999.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1999.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1999.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1999.5

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 1999.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1998.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 1998.8

Language：English   Presentation type：Oral presentation (general)  

Event date： 1998.8

Language：English   Presentation type：Oral presentation (general)  

Event date： 1998.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan