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91.
We First define a continuous extension of the Laquerre polynomials and give some properties of this continuous extension. Then we define a continuous Laguerre transform for square integrable functions, give some properties of this transform and give a sampling theorem that is similar to the well known Shannon-Whittaker Sampling Theorem for Fourier transform. The inverse of this transform is also given. 相似文献
92.
This article is concerned with a boundary-field equation approach to a class of boundary value problems exterior to a thin domain. A prototype of this kind of problems is the interaction problem with a thin elastic structure. We are interested in the asymptotic behavior of the solution when the thickness of the elastic structure approaches to zero. In particular, formal asymptotic expansions will be developed, and their rigorous justification will be considered. As will be seen, the construction of these formal expansions hinges on the solutions of a sequence of exterior Dirichlet problems, which can be treated by employing boundary element methods. On the other hand, the justification of the corresponding formal procedure requires an independence on the thickness of the thin domain for the constant in the Korn inequality. It is shown that in spite of the reduction of the dimensionality of the domain under consideration, this class of problems are, in general, not singular perturbation problems, because of appropriate interface conditions. 相似文献
93.
We report a room-temperature and high-mobility InGaZnO thin-film transistor on flexible substrate. To gain both high gate capacitance and low leakage current, we adopt stacked dielectric of Y2O3/TiO2/Y2O3. This flexible IGZO TFT shows a low threshold voltage of 0.45 V, a small sub-threshold swing of 0.16 V/decade and very high field-effect mobility of 40 cm2/V. Such good performance is mainly contributed by improved gate stack structure and thickness modulation of IGZO channel that reduce the interface trap density without apparent mobility degradation. 相似文献
94.
This study proposes a beam shaper for converting a circle beam profile generated with a Gaussian intensity distribution by an 808 nm diode laser into a line beam profile for silicon surface treatment applications. To produce a hand-held and low-cost device with a large spot-size laser, this study uses a portable optical system consisting of a diode laser source, a collimator, a cylindrical lens, and a plano-convex lens to generate an approximately 40 × 3:5mm2 line beam profile at a working distance of 200 mm. The silicon surface treated by the line-shaped laser beam has significantly reduced reflectance spectra. The proposed system is also suitable for the surface cleaning of materials. 相似文献
95.
Ming-Fei Chen Yu-Pin Chen Wen-Tse Hsiao Shi-Yuan Wu Chun-Wei Hu Zhi-Peng Gu 《Optics and Lasers in Engineering》2008,46(5):410-418
Laser marking is an important branch of laser processing technology, and has been widely used in many fields of industry. Digital signal processor (DSP) is an incredibly fast and powerful microprocessor that can deal with signals in real time. Not only it is portable but has the ability to integrate the processing signals of subsystems. In this research, it is emphasized that we designed a scribing laser marking system based on a DSP in galvanometric marking method. To control the rotating angle of the galvanometric scanning mirrors more accurately, we combine the D/A converter of the DSP with the human–machine interface successfully. The whole marking system is not only inexpensive, but also miniaturized. 相似文献
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The stability of olive oil-in-water (o/w) emulsion stabilized with sucrose fatty acid ester (SFAE) was evaluated through an accelerated ageing test. The stability of the emulsion in this study was examined by the appearance of any phase separation in the emulsion, mean droplet size and rheological properties over one month. The effect of accelerated ageing at 45 ℃ on the emulsion rheological properties was investigated using an amplitude sweep test, a frequency sweep test and a viscometry test. The rheological properties of the emulsion were examined at the one day, one week and one month of storage time. Among the series of emulsions prepared, the emulsion with 2∶8 of water to oil ratio (by weight) is the most stable one, which did not show any of phase separation. The amplitude sweep result shows that there was no significant change of the critical strain of the emulsion throughout one month of storage time. The dynamic properties as well as the steady flow behavior of the emulsion also show no significant changes for over one month of storage time. The mean droplet size of the emulsion remained stable around 2.5 μm within the period of investigation. 相似文献