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Hiroshima, Japan

Hiroshima Kokusai Gakuin University is a private university in Hiroshima, Hiroshima, Japan. The predecessor of the school was founded in 1927. It was chartered as a junior college in 1964 and became a four-year college in 1967. Wikipedia.

Imamura A.,Hiroshima Kokusai Gakuin University | Aoki Y.,Kyushu University
Chemical Physics Letters | Year: 2013

Polyyne oligomers (H2CnH2), with CH 2 group at each end of the oligomer, have been found to give helical molecular orbitals for the HOMO and LUMO and other molecular orbitals around the HOMO and LUMO when the two CH2 groups are tilted from their equilibrium positions. This can be explained by the changes in the symmetry of H2C2m+1H2 from D 2d to D2, the former having degenerate molecular orbitals but the latter having non-degenerate orbitals. These helical molecular orbitals have been pointed out as being a kind of molecular device through which electrons pass. © 2013 Elsevier B.V. All rights reserved. Source

Koseki Y.,Hiroshima Kokusai Gakuin University
Geographical Review of Japan | Year: 2016

With increased imports of agricultural products to Japan, concerns over safety and quality increased. The Ministry of Health, Labour and Welfare introduced "a positive list system" for agricultural chemical residues in food on May 29, 2006. Japan has been working hard to regulate residual agricultural chemicals. This paper examines how Taiwanese mangos are produced and exported to Japan. It also examines how Taiwan's market response to Japan focusing on safety and quality control has been influencing its mangoproducing region and agriculture in general. After Japan introduced the positive list system for agricultural chemical residues, the Executive Yuan Council of Agriculture established a production and exportation system conforming with Japanese safety standards. This mandatory registration system regulates mango exporters and cultivators under mango production contracts, and a pesticide residue inspection by cultivators must be carried out twice before mangos are shipped to Japan. In addition, the exporters and producers share information concerning safety and quality control for mangos. This information is disclosed to consumers through the traceability system of the Executive Yuan Council of Agriculture. In Taiwan's mango-producing region, most growers who sell to both the Japanese and domestic markets use the same production and exportation system along with Japanese safety standards to grow Irwin mangos. Some producers, who are able to add value to their mangos by utilizing the traceability system that ensures food safety, also sell their mangos on the domestic market. This suggests that the traceability system developed for exportation to Japan has resulted in quality assurance that gives high added value to mango producers in Taiwan. Producing and exporting mangos utilizing the Japanese safety standards have therefore been playing a role in enhancing agricultural standards in Taiwan. Changes in the system concerning food safety developed the traceability system and heightened the awareness of producers and exporters of the need for safety and cultivation management. Taiwan's response to Japan focusing heavily on safety has also increased the incomes of mango growers. If Taiwan wants to continue exporting mangos to Japan, it is important for it to see the advantage of spending on labor and costs to ensure safety after the system changes. Moreover, mangos cultivated based on the production and exportation system along with Japanese safety standards have created a new differentiated domestic market. Taiwan's efforts for exportation to Japan with a heavy focus on safety have become one of the reasons why the agriculture sector in Taiwan diversified the market for domestic mangos. Source

Yasuda T.,ASA Research | Yasuda T.,Hiroshima University | Wu C.,ASA Research | Nakagawa N.,Hiroshima Kokusai Gakuin University | Nagamura K.,Hiroshima University
Applied Acoustics | Year: 2010

The tail pipe noise from a commercial automotive muffler was studied experimentally and numerically under the condition of wide open throttle acceleration in the present research. The engine was accelerated from 1000 to 6000 rpm in 30 s at the warm up condition. The transient acoustic characteristics of its exhaust muffler were predicted using one dimensional computational fluid dynamics. To validate the results of the simulation, the transient acoustic characteristics of the exhaust muffler were measured in an anechoic chamber according to the Japanese Standard (JIS D 1616). It was found that the results of simulation are in good agreement with experimental results at the 2nd order of the engine rotational frequency. At the high order of engine speed, differences between the computational and experimental results exist in the high revolution range (from 5000 to 6000 rpm at the 4th order, and from 4200 to 6000 rpm at the 6th order). According to these results, the differences were caused by the flow noise which was not considered in the simulation. Based on the theory of one dimensional CFD model, a simplified model which can provide an acceptable accuracy and save more than 90% of execution time compared with the standard model was proposed for the optimization design to meet the demand of time to market. © 2010 Elsevier Ltd. All rights reserved. Source

Yasuda T.,Hirotec Corporation | Yasuda T.,Hiroshima University | Wu C.,Wuhan University of Technology | Nakagawa N.,Hiroshima Kokusai Gakuin University | Nagamura K.,Hiroshima University
Applied Acoustics | Year: 2013

Tail pipe is a most common structure in mufflers to silence low frequency noise from an engine for its acoustic performance of low-pass filter. Based on the typical structure, a muffler with an interconnecting hole on the tail pipe was proposed to improve its acoustic performance in the present research. Acoustic performances of the proposed muffler were studied experimentally and theoretically in frequency and time domain. It was found that the interconnecting hole enabled the proposed muffler to have a noise attenuation performance of Helmholtz resonator. So the proposed muffler can attenuate the noise of low frequency and middle frequency at the same time. The frequency equation of this structure was derived using the acoustic-electronic analogy. It is useful for estimating the attenuation performance at the stages of predesign or tuning. The influence of structure parameters of the proposed muffler on its acoustic performance was studied. According to the results, the design guideline of this muffler was concluded in the present research. © 2012 Elsevier Ltd. All rights reserved. Source

Min S.,Wuhan Textile University | Nagamura K.,Hiroshima University | Nakagawa N.,Hiroshima Kokusai Gakuin University | Okamura M.,DaikyoNishikawa Coporation
Applied Acoustics | Year: 2013

Polycarbonate (PC) laminate is gradually substituted for the glass as window pane in automobile. Absorption performance of PC pane is poor using resin membrane between two folders of pane because of the low acoustic impedance of membrane. Micro-perforated absorbers can provide high absorption coefficients. However, the depths of air cavity were all over the 50 mm in past studies. In this paper, a compact and efficient micro-perforated membrane (MPM) absorber is designed as a combination of baffle-resonator and Helmholtz-resonator with sub-millimeter holes backed by an air space. Absorption coefficients of MPM absorbers are predicted by equivalent electric-acoustic circuit analysis method. This paper presents three different MPM materials of polypropylene, polyethylene, and carbon polyester respectively. The numerical results shows that absorption performance of PC pane can be improved using double layer MPM absorber and the whole thickness of MPM absorber is not exceed 10 mm to meet the structural requirement of PC pane application in automobile. Crown Copyright © 2012 Published by Elsevier Ltd. All rights reserved. Source

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