Application of the Integrated Diode Synchronous Motor to Traction Drive Motors

In this study, a traction drive electric motor was designed with a new magnet‐free motor design technique where electromagnets are generated on a rotor by utilizing changes in the spatial second harmonic of the magnetic fields. To apply the proposed technique to electric motor design, balancing the rotor and stator magnetomotive force is important. This paper presents design methods for adjusting the rotor and stator magnetomotive forces. A test motor was designed with these design methods and evaluated using a motor bench. The analytical and measurement data indicated that the proposed motor performed comparably to magnet motors.     

Integration of Incinerator Plants and Utilization of Forest Biomass on the Basis of FIT

Feed‐in tariff (FIT) has been enforced in order to promote the utilization of renewable energy since 2012 in Japan. In consideration of FIT, we propose an integration plan for incinerator plants (IPs) with highly efficient power generation for the whole area of a prefecture. The plan includes disposal of forest biomass using the reserve capacity of IPs. The model prefecture's population is set to 1,200,000 and the proportion of the forested area is set to 70% of the model area based on data for northeastern Japan. The present 16 IPs are integrated into three new IPs. A relay transportation (RT) facility for waste is located at a decommissioned IP, and the waste from the area is transported to the new IP. In order to calculate the RT costs, an approximation formula for the RT distance is estimated via the IPs integration study. The plan will realize about 37% cost reduction and 1.8‐fold CO₂ reduction including RT as compared to the plan to update the current IP situation. Forest biomass of 56,500 tons per year, which is about 43% of available forest biomass volume in the model prefecture, can be disposed of at new IPs. On the other hand, enough profit is not expected from the dedicated biomass power generation plant as a result of wood chip processing fees. The plan will help to develop local forestry.     

Composition of Fermented Grape Juice Continuously Produced by Immobilized Lactobacillus casei

Continuous fermentation of grape juice was carried out in a packed bed column system using Lactobacillus casei adsorbed onto ceramic beads. Chemical components in the reaction vessel of this system were compared with those of a free-cell fermentation. No major differences were noted in the principal components. Diacetyl and methionine levels decreased, however, whereas aspartic acid and cysteine increased. Silica levels increased immediately after initiation of the immobilized cell culture due to elution from the ceramic carrier beads. In two of the five trials the reactor was contaminated with Bacillus megaterium.     

Hydrothermal Oxidation of Hf Metal Chips in the Preparation of Monoclinic HfO2 Powders

Fine monoclinic HfO₂ powders were prepared from Hf metal chips by reaction with high-temperature high-pressure water. Dependence of the reaction on temperature-pressure-time was examined in both closed and open systems. Hydrothermal oxidation of Hf proceeded through three stages: the surface oxidation of Hf metal chips with H₂O, the reaction of the Hf with released H₂ to form hydrides, and the succeeding oxidation of the hydrides with H₂O to form HfO₂. Most of the fine HfO₂ powders were, however, considered to be formed by the latter two reactions after the cracking and pulverizing of metal chips associated with hydriding. The difference in the reaction rates between the closed and open systems was explained by taking into account the fugacity relations of H₂ and H₂O in the respective systems.     

Preparation of High-Strength Calcium Phosphate Glass-Ceramics by Unidirectional Crystallization

Unidirectionally crystallized CaO-P₂O₅ glass-ceramics were produced by reheating glass rods between 450° and 580°C (glass transition temperature ∼500°C) under a temperature gradient of 30°C/cm. These glass-ceramics exhibit high bending strength (∼650MN/m²) and toughness. Sample preparation is described and compared with conventional unidirectional solidification of melts. The characteristic mechanical properties are discussed in terms of the texture of the glass-ceramics.     

PERFORMANCE ANALYSIS OF TRAFFIC CONTROL METHODS ON MIXED TRAFFIC CLASSES IN ATM LAN

We treat traffic control methods for the multimedia ATM LAN, in which two service classes are considered; one is for high-speed data transfer based on a fast reservation protocol (FRP service class) and the other is for the continuous bit rate (CBR) traffic such as motion video (CBR service class). Through an analytic method, the performance of the CBR service class traffic is shown to be heavily affected by the FRP service class traffic. Thus, we introduce a reserved bandwidth for the CBR service class to guarantee some appropriate level of performance for the CBR service class. With the reserved bandwidth for CBR service class, the performance of CBR service class can be preserved from being affected by the FRP class traffic load.     

大长高比腔体内的混合流体行进波对流

该文报告大长高比腔体（Г=46）中强非线性状态（ψ=-0．47）混合流体行进波对流图案的数值模拟结果。利用MAC法通过二维流体力学扰动方程组进行了数值模拟。获得了发生在对流发生点附近的线性Counter propagatingwave，出现在分叉图非线性分支上的均匀行进波和发生在分叉图saddle-node附近的局部行进波状态等三种行进波对流图案，并探讨了它们的稳定性。最后将数值模拟结果与实验结果进行了比较。     

Equivalence condition of optimal control problems†

Two optimal control problems which have the same optimal feedback control laws and identical minimum costs are said to be equivalent. The conditions for the equivalence of two optimal control problems have been presented by other authors, but it seems that the equivalence conditions given by other authors are not complete. In this paper, a necessary and sufficient condition for the equivalence classes is derived.     

Reversible Optical Change of Amorphous Red Phosphorus in Reduced Phosphate Glasses

Amorphous red phosphorus formed in reduced phosphate glasses was found to show a photodarkening effect by illuminating the glasses with light approximately equivalent to its absorption edge; the optical transmission edge shifts toward longer wavelengths on illumination, and then a distinct deepening of the reddish color is observable visually. The photo-darkened specimen recovers its original transmission when it is heated at 300° to 350°C. This darkening-restoring process is confirmed to be reversible by repeated illumination and heating. Transmission measurements over a range of elevated temperatures suggest that this optical characteristic of red phosphorus is unique to its amorphous state.     

Development and Microstructural Characterization of High-Thermal-Conductivity Aluminum Nitride Ceramics

The effect of several additives, such as CaC₂, CaO, Y₂O₃, and C, on thermal conductivity of hot-pressed AlN ceramics was investigated. The addition of CaC₂ reductant was found to be useful for achieving high thermal conductivity of 180 W/(m·K) at room temperature. The characterization of AlN ceramics with CaC₂ additive was performed by chemical analysis of Ca, C, and O and microstructural analysis using transmission electron microscopes equipped with an energy-dispersive X-ray analyzer and an electron energy loss spectrometer. The major influence on high thermal conductivity is the disappearance of a thermal barrier caused by oxygen impurities at the grain boundary.