Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

Micro-displacement Characteristics under Tangential Force

Abstract: In this paper, firstly the obtained analytical results are briefly summarised. Next some experimental results are shown developed using finished ceramic surfaces of ZrO{2} and Al{2}O{3} together with SiC. And comparison of obtained experimental results with theoretical analyses and approximate equations introduced in the preceding works was made. The main conclusions are as follows. (1) Little difference can be seen in appearance between the experimental and calculated displacement behaviours, although frictional force of SiC is higher compared with those of other two ceramics and the slope of the curve after macro-slip of SiC is greater than those of the others. (2) Experimental values of tangential stiffness r{g} at the start of increasing the tangential force lie between calculated values by the two contact models. (3) Experimental values of tangential displacement δ{cmax} at the start of macro-slip are larger than those calculated by the two contact models and this is more evident for ZrO{2}.

Temporal change in P‐wave scatterer distribution associated with the M6.1 earthquake near Iwate volcano, northeastern Japan

Abstract: Summary Temporal variation of the scatterer distribution has been detected around the focal area of an M6.1 earthquake, northeastern Japan, by applying semblance analysis to seismic array data. The variation was found in slant-stacked waveforms of two explosions detonated just above the focal area one month before and two months after the M6.1 earthquake. According to geodetic observations, a pressure source that might be a magma reservoir exists beneath this region and its location changed during the observation period. Slant-stacked waveforms are slightly different for the two explosions. The difference suggests that a scatterer contributing to the coda part is shifted towards the east and to greater depths only after three months. In this region, seismic and volcanic activity was very active during the interval between the two explosions. The volcanic activity of Mt Iwate just north of the M6.1 earthquake, which started several months beforehand, continued during this period. It may be considered that scatterer change relates to seismic and/or volcanic activity in the studied area.

Effects of Ozone and/or Soil Water Stress on Growth and Photosynthesis of Fagaus Crenata Seedlings

Abstract: The effects of ozone (O3) and soil water stress, singly and in combination, on the growth and photosynthesis of Fagus crenata seedlings were investigated. Four-year-old seedlings were exposed to charcoal-filtered air (<5 nmol mol-1 O3) or 60 nmol mor-1 O3, 7 hours per day (11:00)-18:00), for 156 days from 10 May to 11 October 1999 in naturally-lit growth chambers at 20/15C (6:00-18:00/18:00-6:00). During the same period, half of the seedlings in each gas treatment received 250 mL of water at the 3-day intervals (wellwatered treatment), while the rest received 175 mL of water at the 3-day intervals (water-stressed treatment). The exposure of the seedlings to O3 caused reductions in the leaf, stem, root and whole-plant dry weights. The net photosynthetic rate at 350 μmol mol-1 CO2, the maximum net photosynthetic rate at saturated CO2- concentration, carboxylation efficiency of photosynthesis and Rubisco content were significantly reduced by the exposure to O3. The soil water stress induced reductions in the stem, bud and whole-plant dry weights, transpiration rate and leaf water potential during the midday. The additive effects of O3 and soil water stress were observed on the dry matter production, leaf gas exchange rates and leaf water potential. As a result, the whole-plant dry weight of the seedlings exposed to both stresses was markedly reduced compared with that of the seedlings exposed to charcoal-filtered air and grown in the well-watered treatment.