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1 – 2 of 2Naoya Watanabe, Yasuhito Takahashi and Koji Fujiwara
This paper aims to propose an effective modeling method of dynamic hysteresis properties for soft magnetic composite (SMC) core using an equivalent circuit representation. Because…
Abstract
Purpose
This paper aims to propose an effective modeling method of dynamic hysteresis properties for soft magnetic composite (SMC) core using an equivalent circuit representation. Because the eddy currents flowing inside iron powder particles should be considered, it is well known that an accurate magnetic field analysis of the SMC core in a wide range of excitation frequency is not easy. To overcome this difficulty, a dynamic hysteresis modeling based on the standard Cauer circuit is investigated.
Design/methodology/approach
In the proposed method, the first inductance represents the static magnetic property of the SMC, and the latter part represents the dynamic effect because of the eddy currents. The values of the circuit elements were determined by an optimization method based on symmetric loops measured at several frequencies. To verify the validity of the proposed modeling method, finite-element analyses of a ring core inductor and an alternating current reactor were performed.
Findings
By comparing the simulated and measured magnetic properties, the necessity to consider magnetic hysteresis in the equivalent circuit model is clarified. Furthermore, the frequency-dependent inductances of practical reactors can be obtained from the finite-element analysis combined with the proposed method.
Originality/value
This paper demonstrates the significance of determining the circuit parameters in the equivalent circuit for dynamic hysteresis modeling based on the measured magnetic properties. The effectiveness of the proposed method is verified by comparing frequency-dependent inductances of two kinds of reactors between the simulation and measurement.
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Keywords
Satomi Fujimori, Suchinda Jarupat Maruo, Toshiaki Watanabe, Naoya Taki, Fumihito Sasamori, Kazuki Kobayashi, Hisaki Akasaki, Masao Okuhara, Ryoji Uchiyama, Kazuki Ashida, Hisaaki Tabuchi and Koji Terasawa
This study aims to establish a Japanese-style healthcare program customized for Japan and Asia under ISO 9001: 2008 (ISO: International Organization for Standardization) to…
Abstract
Purpose
This study aims to establish a Japanese-style healthcare program customized for Japan and Asia under ISO 9001: 2008 (ISO: International Organization for Standardization) to improve problem areas and to inspect the effectiveness of the program. Furthermore, the authors wanted to create this health program using the ISO widely available in Asian countries and make an international contribution.
Design/methodology/approach
The authors implemented a 6- to 10-month health program in Minowa Town, Matsumoto City and Nagano City in Japan. This study assessed findings from pedometric, anthropometric and blood pressure measurements and physical fitness, blood chemistry and brain function tests.
Findings
The comparisons were made by examining the interaction effects between groups of participants. Groups from three regions in Japan showed significant differences on the physical fitness tests; regarding the 10-meter obstacle walk, the results of the Minowa participants showed the greatest improvement and the Matsumoto participants showed the second greatest improvement. In the six-min walk, the time of the Minowa participants significantly improved.
Research limitations/implications
This health education program, which has been conducted by the Japanese authors since 1998, measures anthropometry, brain function and physical fitness and performs blood tests before and after the program and it measures energy consumption with a pedometer during the program. With the aim of improving exercise via encouragement from friends and a sense of community with fellow participants, participants learn together with hands-on training in tai chi and aerobics about the importance of ongoing exercise and proper nutrition. This health education met the Health Education ISO in 2014.
Practical implications
Since 2010, Nagano Prefecture, including Minowa Town, Matsumoto City and Nagano City, where our study was carried out, has been the area with the highest life expectancy rates in Japan.
Social implications
The authors want to make this health promotion through ISO widely available in Asian countries and an international contribution.
Originality/value
This study aimed to appropriately establish a Japanese-style healthcare program under the ISO 9001:2008 to improve problem areas and inspect its effectiveness.
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