A5020471730- Acoustic Wave Resonator Technologies
- Sports Dynamics and Biomechanics
- Turbomachinery Performance and Optimization
- Evolutionary Game Theory and Cooperation
- Sports Performance and Training
- Aerodynamics and Acoustics in Jet Flows
- X-ray Diffraction in Crystallography
- Game Theory and Applications
- Crystallization and Solubility Studies
- Mechanical and Optical Resonators
- Ferroelectric and Piezoelectric Materials
- Sports Analytics and Performance
- Fluid Dynamics and Turbulent Flows
- Microwave Engineering and Waveguides
- Experimental and Theoretical Physics Studies
- Aerodynamics and Fluid Dynamics Research
- Experimental Behavioral Economics Studies
- Crystallography and molecular interactions
- Heat Transfer Mechanisms
- Theoretical and Computational Physics
- GaN-based semiconductor devices and materials
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Advanced Fiber Optic Sensors
- Combustion and flame dynamics
Sumitomo Rubber Industries (Japan)
2014-2023
Yamaguchi University
2020-2023
Doshisha University
2002-2022
Choju Medical Institute
2021-2022
Kyoto University
2012-2020
Showa Corporation
2009-2019
Daido Metal (Japan)
2019
The University of Tokyo
1993-2018
Taiyo Yuden (Japan)
2010-2015
Showa Denko (Japan)
2013-2014
Abstract Thiosulfate ion was used as a substitute for hydrogen sulfide (H2S) to simulate stress corrosion cracking (SCC) of corrosion-resistant alloys (CRAs) and (SSC) high-strength, low-alloy steels. Several SCC tests using variety application techniques showed the brine containing thiosulfate exhibited similar severity H2S in regard when plastic strain applied CRAs. Materials that susceptibility agreed well those H2S. Types 304 (UNS S30400) 316L S31603) stainless steels duplex steel both...
Mixed extension has played an important role in game theory, especially the proof of existence Nash equilibria strategic form games. can be regarded as continuous relaxation a game. Recently, repeated games, class behavior strategies, called zero-determinant was introduced. Zero-determinant strategies unilaterally enforce linear relations between payoffs, and are used to control payoffs players. There many attempts extend so apply them broader situations. Here, we games where action sets...
We have developed a new electrode material, suitable for AlN-based FBARs. The necessary conditions FBAR materials are low density, resistivity, and high acoustic impedance. investigated the influence of on resonant characteristics in FEM simulations experiments. found properties ruthenium (Ru) to be use as In addition, by smoothing surface electrodes, full width at half-maximum (FWHM) X-ray rocking curves AlN films is 2.9/spl deg/ Ru electrodes. using electrodes were an unloaded quality...
Repeated games have provided an explanation how mutual cooperation can be achieved even if defection is more favorable in a one-shot game prisoner's dilemma situation. Recently found zero-determinant strategies substantially been investigated evolutionary theory. The original memory-one unilaterally enforce linear relations between average payoffs of players. Here, we extend the concept to memory-two repeated games. Memory-two correlation functions and at previous round. Examples strategy...
The paper describes how the characteristics of leaky surface acoustic wave (LSAW) propagation depend on thickness Al grating electrodes rotated Y-X LiTaO3. It is shown that loss arising from nature changes parabolically with both electrode and rotation angle becomes zero when are properly determined. This means even thick needed in device design, always realized by determining angle. When 0.07 to 0.1 wavelength for example, LSAWs 40-42 degrees LiTaO3 give without deteriorating other...
The paper describes how the propagation loss /spl alpha/ of leaky surface acoustic wave (LSAW) is dependent upon Al thickness h grating electrodes and rotation angle theta/ for rotated Y-X LiTaO/sub 3/. Since energy leak LSAW originates from coupling slow-shear field component with other components through boundary conditions, zero can be realised when decoupled. This means that optimal giving should change as well electrical conditions. relatively large 0.07-0.1 wavelengths needed present...
This paper describes a novel method for measuring golf swing angular motion in global coordinate system using the 3-D acceleration and velocity detected by local sensor set at grip end of club. Optical direct linear transformation (DLT) is conventional sports motion; however, accurate localization coordinates precise setting infrared high-speed cameras test field are essential. Furthermore, reflectors must be attached to moving object. The itself fine-tuning expensive, but an accurately can...
This paper describes a circuit model for the analysis of nonlinearity in filters based on radio- frequency (RF) bulk acoustic wave (BAW) resonators. The nonlinear output is expressed by current source connected parallel to linear resonator. Amplitude programmed proportional product currents flowing Thus, performed common analysis, even complex device structures. applied ladder-type RF BAW filter, and dependence discussed. Furthermore, this verified through comparison with experiments.
Instabilities due to mutual interactions among the converters and inverters are sometimes observed. A system with multiple can be controlled stably overall when each converter is according energy-based function like Lyapunov function. This paper proposes a new Lyapunov-based digital control method. First, principle derived especially for control. numerical generator reference waveforms then proposed avoid complex analytical operations. applied grid-connected inverter an LCL filter. We also...
A novel temperature-compensated SAW substrate was developed based on bonded LiTaO/sub 3//sapphire. Because of its small TEC (thermal expansion coefficient) and large Young's modulus, sapphire is an ideal material for a support substrate. The frequency temperature characteristics the 3//sapphire application to US-PCS duplexer are described.
This paper proposes simple and precise nonlinear simulation techniques for surface acoustic wave (SAW) duplexers, especially the in-band 3rd order distortion, so-called 'triple beat'. The model is based on nonlinearity of SAW stress vs. strain (nonlinear elasticity SAW), needs just one parameter, which represents coefficient elastic constant. results triple beat 1.9 GHz Personal Communications Service (PCS) duplexers demonstrate fairly good agreement with measurements an accuracy less than 1 dB.
Zero-determinant (ZD) strategies, a recently found novel class of strategies in repeated games, has attracted much attention evolutionary game theory. A ZD strategy unilaterally enforces linear relation between average payoffs players. Although existence and evolutional stability have been studied simple their mathematical properties not well-known yet. For example, what happens when more than one players employ clarified. In this paper, we provide general framework for investigating...
We describe the development of an air-gap type film bulk acoustic resonator (FBAR) filter fabricated using a thin sacrificed layer on flat substrate. In process we focused reducing cost wafer process. Results from both simulations and experiments demonstrate that dome- shaped air gap was formed between substrate surface bottom electrode FBAR structure possible. Even if is used, can be stress control. Consequently, Q-factor at resonance anti-resonance effective k <sup...
A new temperature-compensated SAW substrate for high power applications was developed based on bonded LiTaO3/sapphire. Because of its small thermal expansion coefficient, large Young's modulus, and electric resistivity, sapphire is an ideal material a support substrate. In addition, the conductivity brings efficient heat dissipation. Surface activated bonding used optimized to strongly bond LiTaO3 without any damage or bow. Keywords-SAW; LiTaO3; sapphire; temperature compensation; surface...
We study a Brownian particle passively driven by field obeying the noisy Burgers' equation. demonstrate that system exhibits replica symmetry breaking in path ensemble with initial position of being fixed. The key step proof is modified boundary condition can be exactly mapped onto canonical directed polymers.
The improvement on power durability of SAW filters in order to realize a duplexer is described this study IDT metallization. Compared with the conventional single layer metallizations such as Al-Cu, laminated films are found show higher durability. Many kinds film were tested changing material middle for three layered which top and bottom layers made Al-Cu or pure Al. Among them, two types Al-Cu/Cu/Al-Cu Al/Mg/Al showed best had lifetime 250 times longer than that current film. further...
The paper describes how leaky surface acoustic wave (LSAW) propagation characteristics on LiTaO/sub 3/ depend upon its rotation angle when the Al electrode thickness is increased. It shown that loss arising from nature changes parabolically with both film and angle, becomes zero they are properly chosen. This means even relatively thick electrodes needed, always achieved by determining for LiTO/sub 3/. When 0.07/spl sim/0.1 wavelengths, example, LSAWs 40/spl sim/42/spl deg/ Y-X offer without...
A filter with aluminum nitride thin-film bulk acoustic resonators (FBAR) for the X-band was developed. The FBAR has an air gap beneath resonator to isolate acoustically from a substrate, and is extremely thin operate in X-band. two structural features - sacrificial layer make very order prevent cracking on edge of gap, deformed dome shape by stresses films keep gap. fabricated operated successfully k <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
In our paper, we discuss the temperature coefficient of frequency (TCF) in structure SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /LiNbO xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> overlays. We studied relationship between TCF and film properties measured by Fourier transform infrared spectroscopy (FT-IR) found that changes to atomic structure, such as peak Si-O-Si bond angle, correlated those TCF. The SAW device can be...
In CDMA (code division multiple access), analog, and partly TDMA (time access) cellular phone systems, transmitting receiving are carried out simultaneously. Thus, an antenna duplexer is needed. An using ladder-type SAW filters was first applied in AMPS (Advanced Mobile Phone System)-CDMA system 1998. The package size 9.5 /spl times/ 7.5 2 mm. development of duplexers will require filter designs that enable lower loss a sharper cut-off, electrode materials provide higher power durability,...
This paper describes the DMS (double mode SAW) filter design techniques to achieve ultra-low-loss and steep cut-off characteristics required for Rx in PCS (personal communications service) duplexer. It is first attempt employ filters antenna duplexers mobile phones. demonstrated that common ground inductance L/sub g/ coupling capacitance C/sub c/ between input output terminals of dramatically enhances skirt steepness attenuation lower frequency side pass band. Based on this result, we...