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排序方式: 共有1420条查询结果,搜索用时 15 毫秒
11.
S. W. Cheong E. J. Hilinski A. D. Rollett 《Metallurgical and Materials Transactions A》2003,34(6):1321-1327
This article attempts to determine the mechanisms governing the grain growth process that occurs during lamination annealing
of a cold-rolled, motor-lamination (CRML) steel. A new simulation approach linking a Monte Carlo model with electron backscatter
diffraction (EBSD) scans used as input has been employed to incorporate the effects of crystallographic texture on the simulated
grain growth process. The results from the texture analysis and the computer simulation of the grain growth process indicate
that both stored energy driven grain growth and anisotropic grain boundary growth influence the overall grain growth occurring
during lamination annealing. 相似文献
12.
In arc welding processes, because of the complexity and nonlinearity of heat transfer phenomena, it is often difficult to design an effective control system based upon an exact mathematical model. In this paper, a self-organizing fuzzy control method is proposed to obtain a uniform weld quality by regulation of the surface temperature at a desired level. The proposed control system is designed to comprise a combined structure of the fuzzy SOC with conventional PD control for improving the system's stability. The control experiments show that the proposed controller guarantees a uniform weld quality for various welding conditions. 相似文献
13.
从烧结矿冷却并回收其余热的角度出发,介绍了利用烧结机尾落矿空间,采用喷吹空气装置对烧结矿进行冷却的小型模拟试验,从测出的结果来看,有可能成为一种新的烧结矿冷却方式。 相似文献
14.
H. Khim Boo Bela K. Mikofalvy James W. Summers W. Alan Sell Don H. Mittendorf 《乙烯基与添加剂工艺杂志》1992,14(3):140-144
The separation of PVC from contaminants is one of the most important steps in recycling PVC. Earlier works have shown that one can separate PVC from other polymers by using the X-ray fluorescence technique. However, in many cases, even after careful separation, there is a remaining impurity level of about 0.1% due to the limitations of the separation processes. In many applications, impurities, particularly nonmeltables, cause defects in the PVC matrix and must be removed for best performance and appearance. Melt filtration appears to be the best technique to remove the nonmeltable impurities. 相似文献
15.
Groups of algebraic integers used for coding QAM signals 总被引:2,自引:0,他引:2
Xue-dong Dong Cheong Boon Soh Gunawan E. Li-zhong Tang 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1998,44(5):1848-1860
Linear block codes over Gaussian integers and Eisenstein integers were used for coding over two-dimensional signal space. A group of Gaussian integers with 22n elements was constructed to code quadrature amplitude modulation (QAM) signals such that a differentially coherent method can be applied to demodulate the QAM signals. This paper shows that one subgroup of the multiplicative group of units in the algebraic integer ring of any quadratic number field with unique factorization, modulo the ideal (Pn), can be used to obtain a QAM signal space of 2p2n-2 points, where p is any given odd prime number. Furthermore, one subgroup of the multiplicative group of units in the quotient ring Z[ω]/(pn) can be used to obtain a QAM signal space of 6p2n-2 points; one subgroup of the multiplicative group of units in the quotient ring Z[i](pn) can be used to obtain a QAM signal space of 4p2n-2 points which is symmetrical over the quadrants of the complex plane and useful for differentially coherent detection of QAM signals; the multiplicative group of units in the quotient ring Z[ω]/(2n) can be used to obtain a QAM signal space of 3·22n-2 points, where i=√-1, ω=(-1+√-3)/2=(-1+i√3)/2, p is any given odd prime number, Z[i] and Z[ω] are, respectively, the Gaussian integer ring and the Eisenstein integer ring. These multiplicative groups can also be used to construct block codes over Gaussian integers or Eisenstein integers which are able to correct some error patterns 相似文献
16.
The human chromosome 9 displays the highest degree of structural variability. Four different types of variants are described including pericentric inversion, extra G-positive band in the q arm, additional G-positive band in the p arm and duplication of band 9q21-q22. It is important to demonstrate inheritance from a phenotypically normal individual in order to differentiate between a variant chromosome and an abnormal chromosome. 相似文献
17.
N Schaap A Schattenberg B B?r F Preijers A Geurts van Kessel R van der Maazen T de Boo T de Witte 《Canadian Metallurgical Quarterly》1997,98(3):750-759
One hundred and eighty-one consecutive patients with standard-risk leukaemia were transplanted with HLA-identical sibling grafts depleted of lymphocytes using counter-flow centrifugation. In 116 patients, standard conditioning was intensified by the addition of anthracyclines. Multivariate analysis revealed significantly more acute GVHD > or = grade 2 and a trend towards more chronic GVHD in patients conditioned with the addition of anthracyclines. For all patients the risk for chronic GVHD, but not for acute GVHD increased with a higher number of T cells in the graft. The projected 5-year probability of relapse was significantly lower in the group of patients conditioned with anthracyclines; 26% versus 52% (P = 0.015). In multivariate analysis the addition of anthracyclines to the conditioning regimen was the only significant factor contributing to a lower probability of relapse. The projected 5-year probability of leukaemia-free survival [LFS] in the patients conditioned with and without the addition of anthracyclines was 56% and 36%, respectively (P = 0.004). In multivariate analysis the addition of anthracyclines to the conditioning regimen correlated significantly with a lower number of mixed chimaeras in patients at 6 and 12 months after BMT. Mixed chimaerism at 6 months after transplantation did not significantly correlate with a higher incidence of relapse in further follow-up. In contrast, mixed chimaerism at 12 months after BMT was significantly associated with higher relapse rate. We conclude that the addition of anthracyclines to the conditioning regimen improves outcome of BMT using T-cell-depleted grafts. 相似文献
18.
The concentration-decay and pulse-injection tracer-gas techniques were used to evaluate the effective volume of a zone. Measurements of airflow rates were carried out in an environmental chamber using SF6 as the tracer gas. Results showed that the flow rate estimated from the concentration-decay technique is about 4·5–14·3% higher than actual flow rate if the effective volume of the chamber is assumed to be equal to the physical volume. The effective volume, estimated from tracer-gas measurements, was found to be about 1·5–2·7% higher than the physical volume of the chamber. 相似文献
19.
20.
Statistical analysis of the decision threshold for parallel PN code acquisition in a Rician fading channel is presented. It is shown that in the performance analysis of the acquisition system with reference filtering, the statistical evaluation of the decision threshold seems more appropriate than the approximation of the decision threshold 相似文献