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排序方式: 共有1527条查询结果,搜索用时 15 毫秒
1.
By using mathematical formulae developed in previous studies, certain pollution parameters of dye effluent obtained from reactive dyeing with a single dye can be predicted with good accuracy. In this study, the degree of pollution of reactive dyeing effluent using dye mixtures was also predicted by other approaches, such as linear and non-linear regression. The prediction accuracy was found to be satisfactory. 相似文献
2.
Zhibin Xiong Haitao Liu Chunxiang Zhu Sin J.K.O. 《Electron Devices, IEEE Transactions on》2005,52(12):2629-2633
In this paper, a new polysilicon CMOS self-aligned double-gate thin-film transistor (SA-DG TFT) technology is proposed and experimentally demonstrated. The self-alignment between the top- and bottom-gate is realized by a backlight exposure technique. The structure has an ultrathin channel region (300 /spl Aring/) and a thick source/drain region. Experimental results show that this technology provides excellent current saturation due to a combination of the effective reduction in the drain field and the full depletion of the ultrathin channel. Moreover, for n-channel devices, the SA-DG TFT has a 4.2 times higher on-current (V/sub gs/=20V) as compared to the conventional single-gate TFT. Whereas for the p-channel devices, the SADG TFT has a 3.6 times higher on-current (V/sub gs/=-20V) compared to the conventional single-gate device. 相似文献
3.
Sinéad C. Mac Namara Maria M. Garlock David P. Billington 《Canadian Metallurgical Quarterly》2007,21(2):152-156
Steam generator replacement at nuclear power plants requires large construction openings in nuclear containment structures. This study examines the effects of such openings placed in a 61?cm (2?ft) thick dome of a shield building. The dome is cast in two layers, and the limiting cases of the two layers acting as one and the lower layer carrying the entire load are considered. Without openings, the stresses due to dead load in the structure are very low when compared to the material strength. With openings, the loads are easily redistributed around the opening, and the maximum stresses for the conservative case are between three and four and one-half times larger than in the original structure with no openings. The extent of the affected area around the holes is relatively small. Smooth corners in the openings are necessary to avoid high local stress concentrations. 相似文献
4.
5.
We report an unexpectedly rich variety of new flow patterns on a granular heap that is centrifuged so as to simulate a reduction
in gravity. These surface patterns exhibit coexisting static and flowing regions that depend strongly on centrifugal stress,
but surprisingly not on mass flow rate. A discrete cellular automata model reproduces some of the patterning features and
indicates that subsurface jamming may precipitate the formation of localized frozen patterns on the surface. This model provides
insights into the mechanics of granular flows under controlled stress environment and jammed-to-flowing transitions in granular
media. 相似文献
6.
Finite element analyses of repaired articular surfaces. 总被引:1,自引:0,他引:1
J S Wayne S L Woo M K Kwan 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》1991,205(3):155-162
The response to a compressive load of a repaired cartilage surface, consisting of full-thickness repair tissue adjacent to normal cartilage, was predicted by the u-p finite element method and compared to that of a normal cartilage surface under the same loading conditions. By individually varying the aggregate modulus, permeability and Poisson's ratio for the repair tissue, analyses were performed to assess the contributions of each to the changes in mechanical behaviour. In comparing the repaired to normal surfaces, the presence of a softer repair tissue resulted in increased axial and decreased radial deformations at any given time point, while a repaired surface with an increased permeability compressed more easily due to the increased fluid flow and caused equilibrium to occur sooner. For smaller Poisson's ratio, the axial deformation was not different from normal if the aggregate modulus was the same as normal; however, the radial expansion was reduced as the repair tissue experienced a larger volume change. These results indicate that the presence of repair tissue in a joint surface can have a strong influence on the mechanical behaviour of the surface. 相似文献
7.
8.
In this study, the absorbance of the three-dye mixture effluent from reactive dyeing has been used to predict the residual colour value of the dyeing effluent. The colour values of the dyeing effluent have been predicted in terms of ADMI colour values. The prediction accuracy was found to be satisfactory when some mathematical approaches, such as linear and non-linear regression, were used. 相似文献
9.
10.
An adaptive analog continuous-time biquadratic filter is realized in a 2-μm digital CMOS process for operation at 300 kHz. The biquad implements the notch, bandpass and low-pass transfer functions. The only parameter adapted is the resonant frequency of the biquad, which is identical to the notch frequency and the bandpass center frequency. The update method is based on a least-means-square algorithm which adapts the notch frequency to minimize the power at the notch filter output. The actual update is modified to reduce the circuit complexity to one biquad and one correlator. When the filter is tracking a sinusoid, this update generates a ripple-free gradient that decreases tracking error. Applications include phase-frequency detectors, FM demodulators (linear and frequency shift keying), clock extractors, and frequency acquisition aids for phase-locked loops and Costas loops. Measured results from experimental prototypes are presented. Nonidealities of an all-analog implementation are discussed, along with suggestions to improve performance 相似文献