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31.
An analytical model for the grain-barrier height of the intrinsic poly-Si thin-film transistors (TFTs) is developed, in which the grain-barrier height for the applied gate voltage smaller than the threshold voltage is obtained by solving the charge neutrality equation and the grain-barrier height for the applied gate voltage larger than the threshold voltage is obtained by using the quasi-two-dimensional (2-D) method. Good agreements between experimental and simulation results are obtained for a wide gate voltage range  相似文献   
32.
A technique for SiO2 formation by liquid-phase deposition (LPD) at nearly room temperature for low-temperature processed (LTP) polysilicon thin-film transistor (poly-Si TFT) was developed. LPD SiO2 film with a lower P-etch rate shows a dense structure. LPD SiO2 also exhibits good electrical characteristics. LTP poly-Si thin-film transistors (TFTs) with LPD SiO 2 as the gate insulator have been fabricated and investigated. Their characteristics indicate performance adequate for their use as pixel transistors in liquid crystal displays (LCDs)  相似文献   
33.
Z. Jiang  Q. Chen  A. Moser 《Indoor air》1992,2(3):168-179
In order to cumpare the peformance of different supply diffuers of ventilation air, the airflow passern, temperature stratifiation and contaminant dispersion in a furnitured office ventilated by three kinds of air diffuer were numerically investigated. The air diffuers studied in this paper are a quarter-cylinder displacement diffuer on the floor and mixing diffuers (linear and vortex diffuers) on the ceiling. The heat sources in the of-fice are considered to be 50% convective and 50% radiative. The k-? two-equatwn model of turbulence is employed to predict the turbulent diffusion. The results show that the displacement diffuser provides a rather uniform flow field with low velocify in most areas, and the vertical temperature difference from floor to ceiling is as high as 6 K. With the linear diffuser, the air velociry is high, and the temperature is uniform both horizontally and vertically. The air velocity generated by the vortex diffuser is moderate. The distributions of the temperature and the contaminant are rather uniform.  相似文献   
34.
The augmented drift-diffusion current equation, which includes velocity overshoot effects through the space derivatives of the electric field, cannot be directly extended beyond one dimension. A new formalism is developed which considers the carrier heating and the distribution relaxation effects to obtain a multidimensional augmented drift diffusion current equation. The equivalent mobility containing the velocity overshoot correction is derived from the perturbation analysis on the carrier temperature using the energy balance equation. The issues related to the numerical implementation of this generalized model and the validity of the assumptions are also discussed  相似文献   
35.
36.
DC resistivity, dielectric constant, dielectric loss and positron annihilation spectra of (Ba1−x Ho x )TiO3 ceramics have been measured as a function of holmium concentration x. It has been found that the DC resistivity of (Ba1−x Ho x )TiO3 is strongly dependent on the Ho content: it decreases three orders of magnitude and reaches a minimum at x = 0.4%. Doping with 0.6% holmium increases the permittivity of BaTiO3 by approximately three times (from ∼1,300 to ∼4,000), with only a slight increase in the corresponding dielectric loss. The local electron density and defect concentration estimated using positron annihilation technique conforms well to the features found in the dielectric and resistivity measurements. The results have been discussed in terms of a mixed compensation model.  相似文献   
37.
In this paper, we address agent coordination from a dynamic systems perspective and propose a dynamic coordination model, which is inspired by biological metabolic systems. A new coordination mechanism through dynamic local adjustment (CDLA) is presented, and coordination is achieved when every agent utilizes explicitly the global system dynamics and performs iteratively a dynamic local adjustment procedure. The CDLA mechanism is investigated in an example multiagent shop floor system. The results show that the example manufacturing process is well-coordinated and the coordination approach is practically applicable and effective  相似文献   
38.
Field tests of the transmission performance of the ATSC DTV system have been conducted in Taiwan. The test results as well as comparisons against the NTSC system performance are reported and analyzed. From the measured results the reception characteristics of the DTV can be deduced and can provide guidelines for television stations to design the transmission system, schedule equipment deployment, plan service coverage areas, and improve the reception quality of the digital signal  相似文献   
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40.
以TD—SCDMA既有进展及面临的挑战与NGBWM的发展走向为基础,重点论述自主创新导向下的TD—SCDMA与NGBWM务实发展战略思考。  相似文献   
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