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131.
In this paper, we establish a set of sufficient conditions for the controllability of damped second-order impulsive neutral integrodifferential systems with nonlocal initial conditions in Banach spaces. The approach used is the Sadovskii fixed point theorem combined with a noncompact condition on the cosine family of operators. An example is presented to illustrate the result. 相似文献
132.
The effects of different types of variations in profile and thickness on the amplitude and the dynamic bending stresses of a square cantilever plate excited by a point harmonic load resonance has been investigated. A four-noded plate bending element has been used for the analysis. The response has been determined for the first three modes of vibration. In each case the results obtained for different thickness variations are compared with those of the uniform thickness plate. It is observed that considerable reductions in amplitude and/or bending stresses can be achieved by the proper selection of thickness variation. 相似文献
133.
Equilibrium phase fields of the ternary Pb-Bi-O system were established by long-term equilibration in the temperature range 660-840 K. Using these results, the partial phase diagram of the ternary system has been constructed. The standard molar Gibbs energy of formation of the ternary oxides, 〈Pb5Bi8O17〉 and 〈PbBi12O19〉, was determined by measuring the equilibrium oxygen partial pressures over the relevant phase fields by static manometry in conjunction with a solid oxide electrolyte-based emf cell. Further, the standard molar Gibbs energy of formation of 〈Pb3O4〉 was also measured by the manometric method. The oxide that coexists with the Pb-Bi eutectic alloy (LBE) has been experimentally confirmed as [β-PbO]ss. Using the thermochemical data measured, the compositions of Pb-Bi alloys that coexist with [β-PbO]ss and ternary oxides were derived and reported. 相似文献
134.
The influence of temperature and thickness on the electrical transport properties of 10% excess tin-doped polycrystalline SnTe thin films were investigated. From the observed variation of electrical resistivity and Seebeck coefficient it is concluded that the material exhibits a p-type degenerate behaviour. Using the size effect data, different physical parameters such as Fermi energy, effective mass and scattering parameter were evaluated and compared with the results on SnTe thin films to understand the effect of excess tin. 相似文献
135.
Vibrations of skew plates immersed in water have been studied in the present work. Two skew prism fluid elements have been developed for the above study. As there is no information available on them, a few experiments have been conducted to measure the frequencies of vibration of these plates immersed in water. The results of both the theoretical and experimental investigations have been compared and found to be agreeing reasonably well. The general findings of these plates regarding their aspect ratios, thickness ratios and boundary conditions are discussed. In addition, the influence of skew angles on the vibration of skew plates have been investigated. It has been noticed that the effect of added mass is found to decrease with the increase of skew angle. 相似文献
136.
137.
An 8-MHz seventh-degree elliptic-function low-pass filter is described, demonstrating an approach to low-distortion antialias filtering for high-definition video applications. The filter's performance goals are achieved through the use of circuit design principles that capitalize on the strengths of BiCMOS technology. The integrator circuits composing the filter consist of a new wideband low-distortion transconductor circuit and a unique BiCMOS Miller-stage circuit. Integrator time constants are determined by stable RC products, enabling a simplified filter calibration scheme that is insensitive to temperature-induced variations and requires no phaselock circuits. The prototype filter IC, consisting of seven integrators assembled in an active-ladder configuration, was fabricated in a 10-V, 2-μm 2.5-GHz BiCMOS technology that also features thin-film resistors and polysilicon-plate capacitors. Measured results from the calibrated filter show passband flatness of 0.2 dB, with aberrations of less than ±1 dB over a 100°C temperature range. Stopband attenuation meets its designed goal of 60 dB. Driven by 7-Vpp, differential input signals, the filter exhibits less than -72-dBc third-order intermodulation distortion products at 1 MHz. For 5-Vpp inputs at 4 MHz, third-order intermodulation spurs remain below -65 dBc 相似文献
138.
The photographic negative-mask method of neutralizing the diffraction-halo effect in speckle photography is applied to enhance the quality of Young's fringes obtained in particle-image-velocimetry studies. The improvement of the fringes achieved with the negative-mask method is compared with improvements by the commonly used method of analyzing a contact copy of particle-image-velocimetry specklegrams. Theoretical analysis and experimental results are presented. 相似文献
139.
Multimedia Tools and Applications - With the fast growing technologies in the field of remote sensing, hyperspectral image analysis has made a great breakthrough. It provides accurate and detailed... 相似文献
140.
Multimedia Tools and Applications - Digital images are widely distributed today over the internet and through other mediums. There are powerful digital image processing tools which have made... 相似文献