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981.
982.
983.
984.
Chengkuo Lee Itoh T. Suga T. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(4):553-559
A micromachined lead zirconate titanate (PZT) force sensor for scanning force microscope (SFM) is conceptualized by its piezoelectricity. The fabrication procedure is interpreted, and mechanical characteristics of the micromachined PZT force sensors with various lengths are studied in this paper. A compact SFM is constructed by using the piezoelectric PZT sensor. A very clear image is taken by this SFM. The current study of the micromachined PZT force sensor can be considered as a breakthrough of design of SFM as well as a good example of integrated piezoelectric microdevices 相似文献
985.
Silicon forms the backbone of the microelectronics industry, and possibly, of the optoelectronics industry, hitherto dominated by III/V materials. One of the remaining goals is to build an optical source in silicon. Erbium exhibits luminescent 1.54 μm intra-4f transitions in both silicon and porous silicon. This paper reviews the work which has been carried out in this field and discusses some possible additional applications of erbium-doped silicon in optoelectronics, such as a novel on-chip temperature sensor. 相似文献
986.
Fuzzy inference, a data processing method based on the fuzzy theory that has found wide use in the control field, is reviewed. Consumer electronics, which accounts for most current applications of this concept, does not require very high speeds. Although software running on a conventional microprocessor can perform these inferences, high-speed control applications require much greater speeds. A fuzzy inference date processor that operates at 200000 fuzzy logic inferences per second and features 12-b input and 16-b output resolution is described 相似文献
987.
D.A. Wesley 《Nuclear Engineering and Design》1993,142(2-3)
A proposed methodology and sample results from several plant investigations are presented for evaluating the expected pressure capacity of nuclear power plant components which could potentially be subjected to Interfacing Systems LOCA (ISLOCA) conditions. Included in this evaluation are tanks, heat exchangers, filters, pumps, valves and flanged connections for systems designed for relatively low-pressure, low temperature conditions, but which could possibly be exposed to reactor coolant conditions, either through human error or isolation valve failures. The probabilities of failure, as a function of internal pressure, are evaluated as well as the variabilities associated with them. Leak rates or leak areas are estimated for the controlling modes of failure. Pressure capacities for the pipes and vessels are evaluated using limit-state analyses for the various failure modes considered. The capacities are dependent on several factors, including the material properties, modeling assumptions, and the postulated failure criteria. The failure modes for gasketed-flange connections, valves and pumps do not lend themselves to evaluation by conventional structural mechanics techniques and evaluation must rely primarily on the results from ongoing gasket research test programs and available vendor information and test data. 相似文献
988.
NIKIÉT. Translated from Atomnaya Énergiya, Vol. 75, No. 4, pp. 265-269, October, 1993. 相似文献
989.
A. P. Petrov 《Color research and application》1993,18(6):375-379
Color and Grassmann-Cayley Coordinates of Shape are considered in this article. The image irradiance equation for colored surfaces and the Grassman manifold λ of orbits Q = {B · h + c; detB ≠ 0} Where c is a vector sweeping the color space H, B is a 3 × 3 matrix, and h(x, y) is the color image of a Lambertian surface assumed to be a linear vector-function of the normal vectors. Different orbits Q(n) correspond to different shapes but they are invariant under color and illuminant transformation. Coordinates of an orbit Q in λ can be computed as 3 × 3 (2 × 2, sometimes) determining the elements of which are values of some linear functionals (receptive fields) of h(x, y). Based on the approach, a shape-from-shading algorithm was developed and successfully tested on the threeband color images of various real objects (an egg, cylinders and cones made of paper, etc.). © 1993 John Wiley & Sons, Inc. 相似文献
990.
Poly(ethylene aspartate) [PEA] was synthesized by the melt condensation of D,L-aspartic acid and ethylene glycol. PEA containing pendent amino and carbonyl groups in its repeating chain was used as the polymeric ligand for complexation with transition metal ions, viz. Co(II), Ni(II), Cu(II), Mn(II), Zn(II), Cd(II), Ca(II), Mg(II), Pb(II) and Hg(II). Complexation was found to be most effective in DMSO. The resulting polyester-metal complexes were solid coloured materials which have been characterized by IR spectroscopy, elemental analysis and magnetic susceptibility measurements. The thermal stability of the polyester-metal complexes was investigated by thermogravimetric analysis (TGA). On the basis of the physico-chemical studies, an oxygen and nitrogen coordinated structure for the polyester-metal complexes is proposed. 相似文献