Prototype Experiments on a 1/32‐Scale Model Via‐Wheel Power Transfer Electric Vehicle

Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long charging time. Wireless power transfer from the infrastructure to running EVs is expected to be the solution to these problems. Electric vehicle and electrified roadway (EVER) has been proposed as a wireless power transfer system for EVs while in motion. Via‐wheel power transfer (V‐WPT) is expected to be a wireless power transfer scheme for EVER. We designed and prototyped a 1:32 scale model of a V‐WPT system that consists of an RF inverter, an electrified roadway, a rectifier, and an EV with a dc motor. The output power of the prototype RF inverter was 5.9 W and the dc–RF conversion efficiency was 36.6%. The LC matching circuits for the V‐WPT were designed with two‐port conjugate matching because S₁₁ of the V‐WPT was intrinsically –0.06 dB. After matching, the S₁₁ value was reduced to –21.5 dB. The power transmission efficiency of the V‐WPT system was 75%. The RF–dc conversion efficiency of the rectifier was 62%. The total efficiency of the EVER system was 24.2%.     

A SIMPLE DECISION RULE ON FUZZY EVENTS

Decision making in real problems is done in a fuzzy environment. Thus, Fuzzy-Bayes decision rules have been proposed to cope with a fuzzy state of nature. These decision rules are based on the probability of fuzzy events, or the possibility measure of fuzzy events. Furthermore, a decision rule based on fuzzy utility functions and the possibility distribution of fuzzy events are constructed. However, in these decision rules the fuzziness of the fuzzy expected utility is very big, because these decision rules are based on the extension principle for calculation of the fuzzy expected utility. In this article, avoiding the large fuzziness of the expected utility, we proposed a simple decision rule based on the representation interval of the possibility distributions of fuzzy events and the representation value of the fuzzy utility function. Further, we discuss the application of this simple decision rule to the decision problems, in which the decision maker obtains the one-peak symmetric possibility distribution of a state of nature and the one-peak symmetric membership functions of fuzzy events on a state of nature, by his or her knowledge and his or her belief.     

Changes of soy protein under ultra-high hydraulic pressure

High pressure (<500 MPa) was applied to soy milk and the protein changes were examined. Soy milk remained a liquid within the range of examined pressures, although its viscosity increased when the time of pressurization was less than 10 min. However, the soy milk changed from a liquid to a sol after treatment at 500 MPa for 30 min. the liquid soy milk showed improved emulsifying activity and stability but reduced emulsifying capacity. Sulfhydryl content of this soy milk was increased slightly after anaerobic pressurization. Harder tofu could be made from pressurized soy milk with CaC1₂ than could be made with unpressurized soy milk. Electrophoresis and isoelectrofocusing revealed that soy proteins were dissociated and some of them coagulated by high pressure. Fluorescence analysis also revealed that soy proteins were modified by high pressure to have larger hydrophobic regions. After pressure treatment, soy milk showed a higher affinity for beany flavour components and saponins which would lead to better use of soy milk in soy foods.     

Charge and Discharge Control to Save Regeneration Energy for Overhead Line and Energy Storage Device Hybrid Power Source Three‐Level Inverter

Hybrid power source three‐level inverter is proposed as a main circuit system with energy storage device for increasing regenerative power. This paper proposes a charge and discharge control method to utilize the regenerated energy. The proposed method is verified by experimental tests with a scaled‐down model and numerical simulation.     

Ohmic heating of Japanese white radish Rhaphanus sativus L.

Ohmic heating was applied to Japanese white radish, Rhaphanus sativus L. at 50 Hz-10 kHz and 40 V cm⁻¹ to examine the effects of frequency on the heat generation. Of the frequencies examined, 50 Hz gave the sharpest initial rise of temperature and the shortest time to raise the temperature at the mid-part of radish to 80°C. The heating rates above 60°C were found to be almost the same and linear for all the frequencies. The pressurization (400 MPa, 25°C, for 10 min) of radish eliminated the sharp initial increase of temperature observed at 50 Hz, and gave an almost linear rise of temperature similar to those above 60°C. When radish was treated with a square wave (10 ms with 10 ms interval) of 45 V cm⁻¹ for 30 s, its impedance decreased and never recovered even after storage at room temperature for 20 h. When radish was treated at 50 Hz and 40 V cm⁻¹ until its mid-part reached 30°C, or heated to 80°C in hot water and then cooled to 30°C, ¹H-NMR imaging analysis showed more free movement of liquid components than in untreated radish. These results suggest that the initial rapid heating up at low frequency is caused by the electroporation of radish tissue membrane, resulting in the reduction of its impedance.     

Transient Study of Synchronous Machine Field Characteristic

The type of excitation systems mainly used for synchronous generators are the static excitation system and the blushless excitation system. In both cases, it is important to estimate the field characteristic. The authors derived about new knowledge of three‐phase sudden short circuit and mismatched synchronizing using the electromagnetic transients program (ATP‐EMTP). This paper studied these phenomena.     

STRIPPING RATE OF PROPIONIC ACID FROM STYRENE-DIVINYLBENZENE COPOLYMERIC MICROCAPSULES WITH TRI-W-OCTYL AMINE AS CORE MATERIAL

ABSTRACT

The stripping rate of propionic acid from microcapsules containing tri-n-octyl amine was investigated using distilled water and aqueous NaOH as stripping solutions. The experiments were conducted at 303K. The stripping rate was found to be controlled by diffusion through porous microcapsule membrane and increased with an increase in the concentration of propionic acid in the microcapsules for each solution system. It was found that the stripping rates in aqueous NaOH solution system was higher than in distilled water at the same concentration of propionic acid in microcapsules. The experimental results in the NaOH solution system could be analyzed using a permeation model considering mass transfer accompanied by irreversible instantaneous neutralization reaction between NaOH and the propionic acid/tri-n-octyl amine complex in the microcapsule membrane.