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991.
Ueda M Iwaki M Nishihara T Satoh Y Hashimoto KY 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(4):849-856
This paper describes a circuit model for the analysis of nonlinearity in the filters based on radiofrequency (RF) bulk acoustic wave (BAW) resonators. The nonlinear output is expressed by a current source connected parallel to the linear resonator. Amplitude of the nonlinear current source is programmed proportional to the product of linear currents flowing in the resonator. Thus, the nonlinear analysis is performed by the common linear analysis, even for complex device structures. The analysis is applied to a ladder-type RF BAW filter, and frequency dependence of the nonlinear output is discussed. Furthermore, this analysis is verified through comparison with experiments. 相似文献
992.
Yoshitomo Honda Tomonari Tanaka Tomoko Tokuda Takahiro Kashiwagi Koji Kaida Ayato Hieda Yasuyuki Umezaki Yoshiya Hashimoto Koichi Imai Naoyuki Matsumoto Shunsuke Baba Kimishige Shimizutani 《International journal of molecular sciences》2015,16(6):14143-14157
Catechins are extensively used in health care treatments. Nevertheless, there is scarce information about the feasibility of local administration with polyphenols for bone regeneration therapy, possibly due to lack of effective delivery systems. Here we demonstrated that the epigallocatechin-3-gallate-conjugated gelatin (EGCG/Gel) prepared by an aqueous chemical synthesis using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-morpholinium chloride (DMT-MM) gradually disintegrated with time and facilitated bone formation in a critical size defect of a mouse calvaria. Conjugation of EGCG with the Gel generated cross-linking between the two molecules, thereby leading to a retardation of the degradation of the EGCG/Gel and to a delayed release of EGCG. The prepared EGCG/Gels represented significant osteogenic capability compared with that of the uncross-linked Gel and the cross-linked Gel with uncombined-EGCG. In vitro experiments disclosed that the EGCG/Gel induced osteoblastogenesis of a mouse mesenchymal stem cell line (D1 cells) within 14 days. Using fluorescently-labeled EGCG/Gel, we found that the fraction of EGCG/Gel adsorbed onto the cell membrane of the D1 cells possibly via a Gel-cell interaction. The interaction might confer the long-term effects of EGCG on the cells, resulting in a potent osteogenic capability of the EGCG/Gel in vivo. These results should provide insight into local controlled release of polyphenols for bone therapy. 相似文献
993.
Zhang Longshuai Ding Ning Hashimoto Muneaki Iwasaki Koudai Chikamori Noriyasu Nakata Kazuya Xu Yuzhuan Shi Jiangjian Wu Huijue Luo Yanhong Li Dongmei Fujishima Akira Meng Qingbo 《Nano Research》2018,11(4):2295-2309
Nano Research - Sodium-doped carbon nitride nanotubes (Na x -CNNTs) were prepared by a green and simple two-step method and applied in photocatalytic water splitting for the first time.... 相似文献
994.
Naoki Toyama Shinobu Ohki Masataka Tansho Tadashi Shimizu Tetsuo Umegaki Yoshiyuki Kojima 《International Journal of Hydrogen Energy》2017,42(35):22318-22324
In this study, we investigated the influence of aluminum precursors on structure and acidic properties of hollow silica–alumina composite spheres, as well as their activity for hydrolytic dehydrogenation of ammonia borane. Hollow silica–alumina composite spheres were prepared via the sol–gel method using polystyrene particles as templates. Activities of the hollow spheres prepared using various aluminum precursors for hydrolytic dehydrogenation of ammonia borane were compared. The molar ratios of evolved hydrogen to ammonia borane introduced were 1.0, 2.8, 1.5, and 3.0 in the presence of the hollow spheres prepared using aluminum ethoxide, aluminum isopropoxide, aluminum tributoxide, and aluminum-tri-sec-butoxide, respectively. Hollow spheres prepared using aluminum precursors with branched alkyl groups exhibit more hydrogen evolution than those prepared using aluminum precursors with normal alkyl groups. From the result of solid-state 27Al nuclear magnetic resonance spectra and temperature-programmed desorption of ammonia, 4-coordinated aluminum species are related to Brønsted acid sites, and highly dispersed aluminum species increase the number of Brønsted acid sites. 相似文献
995.
Atsushi Hashimoto Jin Inoue Takuya Funatomi Michihiko Minoh 《International journal of human-computer interaction》2016,32(9):722-733
Sensing the intention of a user’s forthcoming action is a necessary function for systems that assist human physical activity. In this article, a strategy for recipe guidance systems that can predict the forthcoming intended subtask in a cooking task is investigated. The focus is on user accessing objects, that is, touching and releasing objects. Touching can indicate the start of the forthcoming subtask and releasing can indicate the end of the task. The main difficulty lies in the fact that humans may move objects because they are in the way and use cooking tools that are unanticipated by an assistive system. In such cases, the accessed object should not indicate the forthcoming subtask. A method is proposed to track the progress of a task based on the object access history. This enables to eliminate object accesses that are out of context. Simultaneously, the method predicts the forthcoming subtask based on a combination of progress and materials rather than tools and materials. Then, a guidance system that runs as a web service is developed. In experiments, real cooking activities navigated by this system are observed. The Wizard of OZ method is utilized to simulate a system that detects object accesses. The experimental results show that 73.6% accuracy is achieved in the selection of the displayed information. This result supports the use of “access to objects” realize effective intention-sensing systems. 相似文献
996.
997.
Dong Liang Shun'ichi Kaneko Manabu Hashimoto Kenji Iwata Xinyue Zhao Yutaka Satoh 《International Journal of Optomechatronics》2014,8(1):14-29
In this study, a spatial-dependent background model for detecting objects is used in severe imaging conditions. It is robust in the cases of sudden illumination fluctuation and burst motion background. More importantly, it is quite sensitive under the cases of underexposure, low-illumination, and narrow dynamic range, all of which are very common phenomenon using a surveillance camera. The background model maintains statistical models in the form of multiple pixel pairs with few parameters. Experiments using several challenging datasets (Heavy Fog, PETS-2001, AIST-INDOOR, and a real surveillance application) confirm the robust performance in various imaging conditions. 相似文献
998.
Takeshi Ohshima Naoya Iwamoto Shinobu Onoda Tomihiro Kamiya Katsuyasu Kawano 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):2189-2192
N+p and p+n diodes were fabricated on p- and n-type 6H–SiC substrates with epitaxial layers, respectively. The charge induced in the diodes by 9 MeV oxygen (O) and nickel (Ni) ions was measured using Transient Ion Beam Induced Current (TIBIC) to clarify the capability of these diodes as particle detectors. As a result of the TIBIC measurements using 9 MeV O, the Charge Collection Efficiency (CCE) of around 83% was obtained for both p+n and n+p diodes. Since the CCE value includes the consumption of incident ion energy in an Al electrode and the n+ (p+) region as well as the decay of charge in the measurement system, the CCE value obtained in this study indicates that SiC n+p as well as p+n diodes are suitable for particle detectors. On the other hand, in the case of 9 MeV Ni ion irradiation, the CCE for both n+p and p+n diodes decreases due to the Auger recombination in dense electron–hole pairs. 相似文献
999.
Tomoya Komatsu Yasutomo Tanaka Ken-ya Hashimoto Tatsuya Omori Masatsune Yamaguchi 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2009,56(7):1451-1456
This paper proposes a new design technique for a ladder-type filter to reduce the passband width without sacrificing the insertion loss, out-of-band rejection, and steepness of the transition bands. First, it is shown that 2 transmission zeros can be generated by connecting an additional resonator in either series or parallel arm of the ladder filter topology. This new filter topology can be designed systematically by the derived-m transformation. Second, it is demonstrated that the narrow bandwidth, sharp transition bands, and large outof- band rejection are simultaneously realized by applying the present technique to specifically designed ladder-type filters. Finally, this technique is applied to the design of a SAW filter fabricated on the Cu-grating/15°YX-LiNbO3 structure. 相似文献
1000.
Yiliu Wang Hashimoto K.-y. Omori T. Yamaguchi M. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2009,56(4):806-811
This paper describes full-wave analysis of piezoelectric boundary acoustic waves (PBAWs) propagating along a metallic grating sandwiched between 2 semi-infinite layers. In the analysis, the finite element method (FEM) is used for the grating region while the spectral domain analysis (SDA) is applied for an isotropic overlay region as well as a piezoelectric substrate region. The combination of the FEM and SDA makes the numerical analysis very fast and precise. As an example, the analysis was made on the PBAWs propagating in an SiO2 overlay/ Cu grating/rotated Y-cut LiNbO3 structure. It is shown that both the shear-horizontal (SH) type and Rayleigh-type PBAWs are supported in the structure, and that their velocities are very close to each other. Thus spurious responses due to the Rayleigh-type PBAW should completely be suppressed for device implementation. Discussions are made in detail on the influence of Cu grating thickness, substrate rotation angle, and metallization ratio on excitation and propagation characteristics of the SH- and Rayleigh-type PBAWs. 相似文献