Aoyama Gakuin University

About: Aoyama Gakuin University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Superconductivity & Thin film. The organization has 3494 authors who have published 6419 publications receiving 115648 citations. The organization is also known as: Aoyama gakuin daigaku.

Applying New JIT-Toyota's global production strategy: Epoch-making innovation of the work environment

Abstract: In order to strengthen management technology strategy, the author has recently developed a new management technology principle, New JIT, based on TMS, TDS, TPS and TQM-S. In developing ''Global Marketing'' that can win the global competition for quality and cost, the key for domestic and foreign companies is to successfully achieve ''Global Production'' that enables simultaneous production start-up (the same quality and production at optimal locations) throughout the world. This paper analyzes and proves the significance of strategically applying New JIT-a global production strategy activity called AWD6P/J-for epoch-making innovation of the work environment, as verified at Toyota. While many vehicle assembly shops depend on a young, male workforce, innovation in optimizing an aging workforce is a necessary prerequisite of TPS-a production strategy of New JIT. Elements necessary for enhancing work value and motivation, and work energy, including working conditions and work environment (amenities and ergonomics), were investigated through objective survey and analyzed from labor science perspectives.

Thermal Conductivity of Amorphous Indium-Gallium-Zinc Oxide Thin Films

Abstract: We investigated the thermal conductivity of 200-nm-thick amorphous indium–gallium–zinc-oxide (a-IGZO) films. Films with a chemical composition of In:Ga:Zn= 1:1:0.6 were prepared by dc magnetron sputtering using an IGZO ceramic target and an Ar–O2 sputtering gas. The carrier density of the films was systematically controlled from 1014 to >1019 cm-3 by varying the O2 flow ratio. Their Hall mobility was slightly higher than 10 cm2V-1s-1. Those films were sandwiched between 100-nm-thick Mo layers; their thermal diffusivity, measured by a pulsed light heating thermoreflectance technique, was ~5.4×10-7 m2s-1 and was almost independent of the carrier density. The average thermal conductivity was 1.4 Wm-1K-1.

Specific heat and electronic states of superconducting boron-doped silicon carbide

Abstract: The discoveries of superconductivity in the heavily-boron doped semiconductors diamond (C:B) in 2004 [Ekimov et al., Nature (London) 428, 542 (2004)] and silicon (Si:B) in 2006 [Bustarret et al., Nature (London) 444, 465 (2006)] have renewed the interest in the physics of the superconducting state of doped semiconductors. Recently, we discovered superconductivity in the closely related ``mixed'' system heavily boron-doped silcon carbide (SiC:B) [Ren et al., J. Phys. Soc. Jpn. 76, 103710 (2007)]. Interestingly, the latter compound is a type-I superconductor whereas the two aforementioned materials are type II. In this paper, we present an extensive analysis of our recent specific-heat study, as well as the band structure and expected Fermi surfaces. We observe an apparent quadratic temperature dependence of the electronic specific heat in the superconducting state. Possible reasons are a nodal gap structure or a residual density of states due to nonsuperconducting parts of the sample. The basic superconducting parameters are estimated in a Ginzburg-Landau framework. We compare and discuss our results with those reported for C:B and Si:B. Finally, we comment on possible origins of the difference in the superconductivity of SiC:B compared to the two ``parent'' materials C:B and Si:B.

On the implications of late internal dissipation for shallow-decay afterglow emission and associated high-energy gamma-ray signals

Abstract: The origin of the shallow-decay emission during early X-ray afterglows has been an open issue since the launch of the Swift satellite. One of the appealing models is the late internal dissipation model, where X-ray emission during the shallow-decay phase is attributed to internal dissipation, analogous to the prompt gamma-ray emission. We discuss possible scenarios of the late prompt emission, such as late internal shocks, magnetic reconnection, and photospheric dissipation. We also consider the consequences of late dissipation and a two-component (early and late) jet model for the high-energy (GeV-TeV) emission. We study not only synchrotron self-Compton (SSC) emission from the early and late jets but also external inverse-Compton (EIC) emission, which is naturally predicted in the late dissipation model. For the latter, we perform numerical calculations taking into account the equal-arrival-time surface of EIC photons and show that the EIC component typically has a peak at ~1-100 GeV which may dominate over the SSC components. We demonstrate that very high energy gamma rays from both these components are detectable for nearby and/or energetic gamma-ray bursts, with current and future Cherenkov detectors such as MAGIC, VERITAS, CTA, and HAWC, and possibly Fermi. Although the expected event rate would not be large, detections should be useful as a test of the model. Multi-wavelength observations using both the ground-based telescopes and the Swift and/or Fermi satellites are also important to constrain the models.

Synergistic effects of catalysts and plasmas on the synthesis of ammonia and hydrazine

Abstract: The synergistic effects o1 driving frequency of the discharge and catalysis of iron and molybdenum wires when then are placed in nitrogen-h ydrogen radio-frequency and microwave plasmas mere investigated. The ammonia Yield increased in the plasmas prepared using both driving frequencies. but the hydrazine yield increased only in fire radio-frequency discharge with the catalysts. The direct adsorption of NHx formed in the plasma on the catalyst surface followed by the formation of NH3 and N2H4 are considered as a reaction scheme in the radio-frequency discharge. On the other hand, the adsorption of N atoms and/or formation of the metal- N bond favors the formation of ammonia but does not affect the hydrazine formation in the microwave discharge.