Toyota

About: Toyota is a company organization based out in Safenwil, Switzerland. It is known for research contribution in the topics: Internal combustion engine & Battery (electricity). The organization has 40032 authors who have published 55003 publications receiving 735317 citations. The organization is also known as: Toyota Motor Corporation & Toyota Jidosha KK.

Integrated Robust Control of Active Rear Wheel Steering and Direct Yaw Moment Control

Abstract: SUMMARY An integrated control system of active rear wheel steering (4WS) and direct yaw moment control (DYC) is presented in this paper. Because of the tire nonlinearity that is mainly due to the saturation of cornering forces, vehicle handling performance is improved but limited to a certain extent only by steering control. Direct yaw moment control using braking and/or driving forces is effective not only in linear but also nonlinear ranges of tire friction circle. The proposed control system is a model matching controller which makes the vehicle follow the desired dynamic model by the state feedback of both yaw rate and side slip angle. Various computer simulations are carried out and show that vehicle handling performance is much improved by the integrated control system.

Thermoelectric performance of Bi- and Na-substituted Ca3Co4O9 improved through ceramic texturing

Abstract: Plate-like particles of Ca3Co4O9 have been prepared in which Bi and Na were partially substituted for Ca to improve the thermoelectric performance. Successfully fabricated dense and highly textured ceramics have been obtained by combining the templated grain growth technique (TGG) with hot-pressing (HP). Ca3Co4O9 single crystals, which have alternating layers of Co–O and Ca–Co–O in the direction of the c-axis, show high electrical conductivity along the layer compared with that across the layer. Hence, a highly oriented TGG + HP specimen showed high electrical conductivity compared with the specimen sintered under uniaxial pressure (UP + PLS). The improved electrical conductivity with high Seebeck coefficient of the highly oriented specimen (TGG + HP) gave a high thermoelectric power factor of 5.9 × 10−4 W m−1 K−2 at 1073 K. The figures-of-merit at 773 K and 1073 K were calculated to be 8.54 × 10−5 K−1 (ZT = 0.066 at 773 K) and 1.69 × 10−4 K−1 (ZT = 0.18 at 1073 K), respectively. These values are quite high among Ca–Co–O polycrystalline systems reported so far.

Effect of GGA on the half-metallicity of the itinerant ferromagnet CoS 2

Abstract: The half-metallicity of ${\mathrm{CoS}}_{2},$ important for its possible use in spintronic applications, is investigated by means of density functional full-potential linearized augmented plane wave calculations within both the local spin-density approximation (LSDA) and the generalized gradient approximation (GGA). In contrast with earlier and our own predictions employing the LSDA, we find that ${\mathrm{CoS}}_{2}$ is clearly half-metallic with use of the GGA for the exchange-correlation functional. While the GGA induced modifications of the band structure are significant, they are limited to only the ${e}_{g\ensuremath{\downarrow}}$ state which is responsible for producing the half-metallicity, while leaving all other features the same as those obtained by LSDA. We address the recently measured reflectivity spectra and rectify the assignments given for their underlying optical transitions.

High efficiency and high concentration in photovoltaics

Abstract: In this paper, we present the state-of-the-art of multijunction solar cells and the future prospects of this technology. Their use in terrestrial applications will likely be for concentrators operating at very high concentrations. Some trends are also discussed and we present a cost calculation showing that highly efficient cells under very high concentration would be able to produce electricity at costs competitive with electricity generation costs for some utilities.