Rotor-dynamic fluid force (RD fluid force) of turbomachinery is one of the causes of the shaft vibration problem. Bulk flow theory is the method for analyzing this RD fluid force, and it has been widely used in the design stage of machine. The conventional bulk flow theory has been carried out under the assumption of concentric circular shaft's orbit with a small amplitude. However, actual rotating machinery's operating condition often does not hold this assumption, for example, existence of static load on the machinery causes static eccentricity. In particular, when such a static eccentricity is significant, the nonlinearity of RD fluid force may increase and become non-negligible. Therefore, conventional bulk flow theory is not applicable for the analysis of the RD fluid force in such a situation. In this paper, the RD fluid force of the annular plain seal in the case of circular whirling orbit with static eccentricity is investigated. The case with both the significant static eccentricity and the moderate whirling amplitude is considered, and the perturbation analysis of the bulk-flow theory is extended to investigate the RD fluid force in such cases. In this analysis, the assumption of the perturbation solution is extended to both static terms and whirling terms up to the third order. Then, the additional terms are caused by the coupling of these terms through nonlinearity, and these three kinds of terms are considered in the extended perturbation analysis of the bulk flow theory. As a result, a set of nonlinear analytical equations of the extended perturbation analysis of the bulk flow theory, for the case with both the significant static eccentricity and the moderate whirling amplitude, is deduced. The RD fluid force for such cases is analyzed, and the occurrence of constant component, backward synchronous component, and super-harmonic components in the RD fluid force is observed in addition to the forward synchronous component. The representation of RD fluid force coefficients (RD coefficients) are modified for the case with significant static eccentricity, and the variation of RD fluid force coefficients for the magnitude of static eccentricity is analyzed. These analytical results of RD fluid force and its RD coefficients are compared with the numerical results using finite difference analysis and experimental results. As a result, the validity of the extended perturbation analysis of the bulk-flow theory for the case with both the significant static eccentricity and the moderate whirling amplitude is confirmed.

We studied EL properties of organic light-emitting diodes using a semi-transparent metal anode and conductive polymer instead of indium tin oxide. A metal anode and conductive polymer are thought to be more suitable for flexible organic light-emitting diodes than indium tin oxide. We fabricated organic light-emitting diodes using a semi-transparent metal anode and conductive polymer anode by vacuum-deposition method and spin-coat method, respectively. Ag thin film is one of optimal metals for the transparent anode because Ag has the lowest resistivity in all metals. The transmittance of composite anode can be improved by combining Ag thin film and an oxide semiconductor with high refractive index. We chose TiOz with a high rehctive index as a semiconductor. A conductive polymer has high conductivity and mechanical flexibility. The organic light-emitting diodes using the semi-transparent anode have ahnost the same performance as those using indium tin oxide.Moreover, the metal anode was speculated to have more cnrrent injection than indium tin oxide.

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Community-level decentralized and self-reliant energy network is expected to contribute to create a sustainable community as well as its self-vitalization and energy resiliency. But implementation of this system requires consensus among variety of stakeholders and long payback period, which are major hurdles. This study proposes the following concept and methods; (1) PPP business scheme consisting of two types of actors; "community-level energy network infrastructure operating company" and "on-site energy production and service providers" (2) Proper reallocation of cost and co-benefits among stakeholders by taking advantage of opportunities of adjusting tariffs, taxes, subsidies for the purpose of equalizing each stakeholder's B/C.