http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Flow-induced Vibration of a High-speed Train Running in a Tunnel
Takeyuki KODERA,Hiroki NAGAI,Keisuke-ASAI,Osamu Terashima 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-
In recent years, flow-induced vibration on the tail car of a high-speed train cruising in a tunnel has become a critical aerodynamic problem because it makes a ride comfort of the train poor. To further increase the train speed, it is required to identify the cause of this phenomenon and take necessary countermeasures. The objective of the present study is to clarify the effects of the tunnel wall on vibrations of a high-speed train running inside a tunnel. We conducted wind tunnel tests of a simplified train model with a flat plate simulating the effect of tunnel wall. Pressure transducers were used to measure unsteady pressure fluctuations on the tunnel wall and Pressure Sensitive Paint (PSP) was applied to measure time-averaged surface pressure distribution on the train model. In addition, we conducted Large Eddy Simulation (LES) calculation for the same model and test condition. In the experiment, pressure fluctuations with the Strouhal number similar to the actual case were observed near the tail car locations. The results of LES calculation indicated that LES could reconstruct the spectrum of pressure fluctuation that observed in the experiment. It was suggested from these results that the vibrations on the tail car were caused by the interaction of the flow separated from the tunnel side of the tail car with the tunnel wall.
Masamichi Kodera,Kosuke Watanabe,Maxence Lassiège,Saman Alavi,Ryo Ohmura 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.81 No.-
Interfacial tension is one of the most important physical properties for high-precision simulations todevelop the methods of preventing plugging of pipelines in the oil and natural gas industry. This paperreports experimental data with the pendant drop method for the interfacial tension of adecane + methane + water system at temperatures between 278.2 K to 298.2 K and pressures up to10 MPa. The data show that in this temperature range the interfacial tension in the decane + methane+ water system decreases almost linearly with increasing temperature. The results also show that byincreasing the pressure of methane, the interfacial tension decreases from 53.98 mN m 1 to50.23 mN m 1 at 283.2 K and 52.23 mN m 1 to 49.74 mN m 1 at 288.2 K. The nature of the methanepressure dependence of the interfacial tension changes for pressures above around 2.00 MPa. Theinterfacial tension decreases with the pressure up to 2.00 MPa, but has no pressure dependence above2.00 MPa. It may be inferred that the decane/water interface is saturated with methane at pressuresaround 2.00 MPa and at higher pressure the interfacial tension is no longer affected by the presence ofmethane.
Kawai, Kiyohiko,Kodera, Haruka,Majima, Tetsuro American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.40
<P>By decreasing the HOMO energy gap between the base-pairs to increase the charge conductivity of DNA, the positive charge photochemically generated in DNA can be made to migrate along the π-way of DNA over long distances to form a long-lived charge-separated state. By fine-tuning the kinetics of the charge-transfer reactions, we designed a functionalized DNA system in which absorbed photon energy is converted into chemical energy to form I−I covalent bonds, where more than 100 I<SUB>2</SUB> molecules were produced per functionalized DNA. Utilizing the fact that charge-transfer kinetics through DNA is sensitive to the presence of a single mismatch that causes the perturbation of the π-stacks, single nucleotide polymorphisms (SNPs) in genomic sequences were detected by measuring the photon energy conversion efficiency in DNA by a conventional starch iodine method.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-40/ja105850d/production/images/medium/ja-2010-05850d_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja105850d'>ACS Electronic Supporting Info</A></P>