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1.
The stress-optical coefficients of RO-Pz05 glasses (R = Mg, Ca, Sr, Ba, and Zn) were measured, and the photoelasticity mechanisms were analyzed based on the equation expressing the relation among the photoelastic constants, the elastic moduli, and the refractive index of glasses. No simple relation was found between the stress-optical coefficient and the elastic modulus, indicating that the factor (p – q), where p and q are the Neumann strain-optical coefficients, is important. The change of (p – q) with glass composition is governed mainly by changes in the effect of the atoms, rather than the lattice. The atomic effect increases with decreasing radius of the divalent cation, except for Zn2+. The ZnO-containing glasses exhibit extraordinarily large atomic effects. The photo-elasticity mechanism is discussed in relation to the nature of the chemical bonds.  相似文献   
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We developed the 550‐kV disconnectors that strengthened earthquake proofing by the addition of the damper unit and weight reduction of conductive part based on the damage of the 550‐kV disconnectors by the Great East Japan earthquake (March 11, 2011) and inspected the earthquake proofing performance by shake table test. In shake table test, we performed the test by the artificial seismic wave that varied in phase characteristic in addition to the test by resonance method. And, in a high‐level earthquake area, we analyzed it about the influence that a phase characteristic of the artificial seismic wave gave to stress to occur in disconnectors. As a result, it is thought that the stress to occur in disconnectors is decided by a primary natural frequency basically because a bending strain to occur to the disconnectors in the time when the resonance frequency ingredient becomes the big acceleration response value grows big. But, on a particular phase condition, it was confirmed that the bending strain to occur in disconnectors might grow big conspicuously. As for this, the possibility is thought about by influence of higher natural frequency doing superposition.  相似文献   
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Vascular calcification is associated with a poor prognosis in dialysis patients. It can be assessed with computed tomography but simple inoffice techniques may provide useful information. We compared the results obtained with a simple noninvasive technique with those obtained using multidetector computed tomography for aortic arch calcification volume (AoACV) in chronic hemodialysis (HD) patients. The enrolled study subjects were 63 (32 men and 31 women) maintenance HD patients. Calcification of the aortic arch was semiquantitatively estimated with a AoAC score (AoACS) on plain chest radiology. The AoACV was increased, with a mean value of 6.6 ranging from 0% to 36.5%. The coefficient of intraobserver variation was less than 2.5%. Aortic arch calcification score was highly correlated with AoACV (r=0.635, P<0.001). Multiple regression analysis showed age (F value=12.62, P<0.001) and pulse pressure (F value=4.54, P=0.037) to be significant independent determinants of AoACS. In conclusion, a simple measurement of AoACS may be useful for inoffice imaging to choose a therapeutic regimen in HD patients.  相似文献   
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Since the output of photovoltaic (PV) generation includes power fluctuations caused by natural conditions, the installation of PV on a large scale is expected to affect load frequency control of the power grid. One method of compensating power fluctuations is the use of energy storage (ES), such as batteries and capacitors. A power fluctuation compensation system composed of an electrical double layer capacitor energy storage system (ESS) and a Li‐ion battery energy storage system is considered. The power loss characteristics of both ESSs during power fluctuation compensation are modeled by equivalent circuits based on ES impedance spectra. The models are validated by experiments simulating power fluctuation compensation. Using these ES models, simulations were carried out to determine the power fluctuation dispatch method between the two ESSs and the capacity of the ESSs in consideration of power loss minimization.  相似文献   
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The feedback stabilization problem for a non-linear elastic distributed parameter system including a destabilizing effect is studied. The model is formulated as an evolution equation in a Hilbert space. Semigroup theory is used to investigate an initial value problem for the equation. Moreover, a control system with a finite dimensional controller is constructed. It is then proved that the state of the overall system converges to zero with a desirable exponential decay rate as time tends to infinity.  相似文献   
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The reactive evaporation method of injected metal powders was investigated for preparing oxide nanoparticles. The method has advantages such as evaporation is enhancement of the injected powder owing to exothermic reaction heat of the metal powder oxidation in induction thermal plasmas. Tangential gas flow injection to the plasma tail flame controls the diameter and the yield of the oxide nanoparticles. The purpose of this research is to investigate the effect of the injection gas flow on the preparation mechanism of oxide nanoparticles in thermal plasmas by experimental work and numerical analysis. An increase in the flow rate of the injection gas leads to an increase in the diameter as well as the yield of the prepared nanoparticles. Numerical analysis for nucleation and growth provides the preparation mechanism of the oxide nanoparticles; however, a more sophisticated model should be developed.  相似文献   
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It is of prime importance to maintain voltage profile within the proper range in distribution systems with a large amount of photovoltaics and electric vehicles (EVs). In particular, there is a possibility that line drop compensation (LDC) logic, which is utilized for the control of load ratio tap transformer (LRT) does not work properly when reverse power flow is included partially. Hence, in this paper, we have developed a new LRT control method based on the sensor information supposing that some section switchgears with sensors are introduced in the future distribution systems. Specifically, the extreme value of voltage profile is estimated by convergence calculation in the section between the section switchgear with sensor and LRT. Moreover, the voltage at the end node can be estimated by LDC method using sensor information of section switchgear. The proposed method was tested using a distribution system model and its effectiveness was shown.  相似文献   
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