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101.
Yi-Cheng Liou Jen-Hsien Chen Yi-Chen Huang Chi-Ting Wu Yow-Renn Chen 《Journal of Electroceramics》2006,16(3):213-220
Pb(Ni1/3Nb2/3)0.72Ti0.28O3 (PNNT) perovskite ceramics produced by a reaction-sintering process were investigated. Without any calcination, the mixture
of PbO, Ni(NO3)2, Nb2O5 and TiO2 was pressed and sintered directly into PNNT ceramics. PNNT ceramics of 100% perovskite phase were obtained. For PNNT sintered
for 2 h in PbO compensated atmosphere, maximum density reaches a value 8.49 g/cm3 (99.8% of the theoretical value) at 1250∘C. A maximum dielectric constant 20600 occurred around 37∘C at 1 kHz in PNNT sintered at 1250∘C for 2 h. 相似文献
102.
Soo-Chang Pei Lin-Gwo Liou 《IEEE transactions on image processing》1997,6(10):1358-1363
The goal of three-dimensional (3-D) motion segmentation is to identify the image areas projected by different moving objects in 3-D space. However, many prevailing methods merely detected the discontinuity of optical flow field and usually considered these boundaries as that produced by different 3-D motions. In fact, the flow discontinuity can be generated either by two different 3-D motions or by the structural discontinuity on the same moving object. The wrong identification causes several problems in 3-D motion estimation. A simple method called the extrapolation and subtraction (ES) technique is proposed to solve these problems. The input image flow field is first partitioned into several functionally analytic regions. Each analytic region is assumed to be projected by a roughly planar patch moving in 3-D space. Based on the parameterization of these analytic flow fields, the ES technique provides a very simple and fast method to test the 3-D motion compatibility between two interested analytic flow fields. 相似文献
103.
Cheng-Yuan Liou Hsin-Chang Yang 《IEEE transactions on pattern analysis and machine intelligence》1996,18(9):941-945
In this work we present a self-organization matching approach to accomplish the recognition of handprinted characters drawn with thick strokes. This approach is used to flex the unknown handprinted character toward matching its object characters gradually. The extracted character features used in the self-organization matching are center loci, orientation, and major axes of ellipses which fit the inked area of the patterns. Simulations provide encouraging results using the proposed method 相似文献
104.
Xiaofang Gao Juin J. Liou Joe Bernier Gregg Croft Waisum Wong Satya Vishwanathan 《Microelectronics Reliability》2003,43(5):725-733
Diodes are key components in on-chip electrostatic discharge (ESD) protection design. As the operating frequency of the microchip being protected against the ESD continues to increase, the parasitic capacitance associated with the diodes in the ESD structure starts to impose problems for RF operation. This paper presents a systematic approach to optimize the diode structure for minimal parasitic capacitance based on the requirements of breakdown voltage and heat dissipation. Device simulator Atlas with mix-mode simulation capability is calibrated against measurement data and used to carry out the optimization. An optimized diode structure with a parasitic capacitance of less than 30 fF at an operating frequency of 10 GHz and ESD charging voltage of 1 kV has been suggested. Furthermore, a case study to implement and optimize the ESD protection structure based on an existing 0.13-μm CMOS technology has been presented and verified. 相似文献
105.
Yan-Lun Liou Jyun-Cheng Liou Jin-Hua Huang I-Nan Lin 《Diamond and Related Materials》2008,17(4-5):776-781
Field emission characteristics of ultra-nanocrystalline diamond (UNCD) have recently caught much attraction due to its importance in technological applications. In this work, we have fabricated lateral-field emitters comprised of UNCD films, which were deposited in CH4/Ar medium by microwave plasma-enhanced chemical vapor deposition method. The substrates, silicon-on-insulator (SOI) or SiO2-coated silicon, were pre-treated by mixed-powders-ultrasonication process for forming diamond nuclei to facilitate the synthesis of UNCD films on these substrates. Lateral electron field emitters can thus be fabricated either on silicon-on-insulator (SOI) or silicon substrates. The lateral emitters thus obtained possess large field enhancement factor (β = 1500–1721) and exhibit good electron field emission properties, regardless of the substrate materials used. The electron field emission can be turned on at 5.25–5.50 V/μm, attaining 5500–6000 mA/mm2 at 12.5 V/μm (100 V applied voltage). 相似文献
106.
Recent growth in RF applications has increased the use of spiral inductors and thus demanded a more accurate model for such devices. In this paper, the authors focus on the model development of spiral inductors with symmetrical terminals, but the same approach can be applied readily to asymmetrical inductors. Relevant and important physics such as the current crowding in metal line, frequency-dependent permittivity in oxide, and overlap parasitics are accounted for. Experimental data and results calculated from the existing inductor models are included in support of the model development. 相似文献
107.
A theory based on a Fokker-Planck equation has been developed to analyze the two-mode operation of a Fabry-Perot/distributed-feedback (FP/DFB) laser. Simultaneous oscillation of the DFB mode and the FP mode near the gain peak with negligible mode power fluctuation can be achieved if the DFB mode is detuned sufficiently from the gain peak. Calculated results for the design of stable two-wavelength lasers are presented 相似文献
108.
The junction field-effect transistor (JFET) has isolated top- and bottom-gate terminals and therefore is useful for signal mixing applications. Existing models for the four-terminal JFET often have the same form as the three-terminal JFET model, however, in which only a single pinch-off voltage is used to describe the current-voltage characteristics. In this paper, a more general four-terminal JFET model is developed. Two different pinch-off voltages are involved in the improved model to account more comprehensively for the effects of both depletion regions associated with the top- and bottom-gate junctions. Results simulated from a device simulator are also included in support of the model 相似文献
109.
Kou-Fu Liou Tsung-Yu Hsiao Chien-Hong Cheng 《Fullerenes, Nanotubes and Carbon Nanostructures》1998,6(2):351-359
Treatment of [60]fullerene with ethyl trans, trans-hexa-2,4-dienoate (1) and methyl trans, trans-octa-2,4-dienoate (2) at 70 ∼ 100 °C afforded products 3 and 4, respectively, which are resulted from Diels-Alder addition of the dienoates to a 6/6 ring junction of [60]fullerene. 相似文献
110.