Solar energy is stored into underground energy piles using heat dissipation pipes embedded beneath pavements as solar heat collectors in summer. Because those l arge inner diameter steel energy piles for a bridge stand close to each other, thermal interference occurs between them. Accordingly, the heat stored under the ground is not released quickly and can be used for snow-melting and de-icing on road in winter. In this paper, the numerical simulations were carried out, taking into account radiate, sensible, latent and conductive heat fluxes that were estimated using weather data. Those calculated results agreed well with the experimental ones in the snow-melting area of 1,896 m² during 2 years.

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 The main method to reduce the blasting charge noise which occurs in a tunnel under construction is to install the sound insulation door in the tunnel. However, the numerical analysis technique to predict the accurate effect of the transmission loss in the sound insulation door is not established. In this study, we measured the blasting charge noise and the vibration of the sound insulation door in the tunnel with the blasting charge, and performed analysis and modified acoustic feature. In addition, we reproduced the noise reduction effect of the sound insulation door by statistical energy analysis method and confirmed that numerical simulation is possible by this procedure.

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 The effects of the luminous color and luminance of LED (Light Emitting Diode) lighting on the oviposition of two firefly species, Luciola cruciata and Luciola lateralis, were studied in the laboratory. Tests were conducted using five colors of LED ray, namely white, blue, green, yellow and red. One female and three males of the firefly were put in the polystyrene case, and illuminated by LED lighting every evening. The presence of the fertilization of fire fly's egg and the number of larvae of the firefly that had hatched from the egg were examined. Females of L. cruciata did not oviposit the fertilized eggs under the yellow LED of 0.11x and the white, blue and green LED of 20 lx. Females of L. lateralis did not oviposit the fertilized eggs under the blue LED of 10lx. The present study suggested that the copulatory behavior of L. cruciata was disturbed by the illumination of the yellow LED as well as the high-pressure sodium lamp for road lighting.

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 This study was conducted to evaluate shear stress working on submerged hollow fibre membrane by CFD (Computation Fluid Dynamics) method in MBRs. Shear stress on hollow fibre membrane caused by aeration was measured directly using a two-direction load sensor. The measurement of water-phase flow velocity was done also by using laser doppler velocimeter. It was confirmed that the shear stress was possible to be evaluated from the water-phase flow velocityby the result of comparison of time average shear stress actually measured with one hollow fibre membrane and the one calculated by the water-phase flow velocity. In the estimation of the water-phase flow velocity using the CFD method, time average water-phase flow velocity estimated by consideration of the fluid resistance of the membrane module nearly coincided with the measured values, and it was shown that it was possible to be estimated also within the membrane module. Moreover, the measured shear stress and drag force well coincided with the values calculated from the estimated water-phase flow velocity outside of membrane module and in the center of membrane module, and it was suggested that the shear stress on the hollow fibre membrane could be estimated by the CFD method in MBRs.

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 The authors examined whether decomposition of rayon in environment is suppressed by coating it with antimicrobial agent DC5700 and poval (PVA). When the rayon samples coated with DC5700 were decomposed in activated sludge or bark compost toge ther with non-coated samples, the coated samples needed longer time for the decomposition comparing to the non-coated samples under the environmental condition whose water content is 56% or less. Moreov er, PVA coating together with DC5700 further extended the decomposition time of rayon samples under the condition whose water content is 40% or less. The dyeing test of DC5700 using bromphenol blue indicated that PVA coating together with DC5700 prevented DC5700 from removing from the rayon su rface under the low-water-con tent condition and thus the double coating sample was decomposed slowly.

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