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61.
62.
直接斜率波前复原算法的控制效果分析 总被引:7,自引:0,他引:7
建立自适应光学系统功率谱抑制函数的概念,分析了采用直接斜率波前复原算法的自适应当光学系统的控制效果,理论分析与61单元自适应光学系统上的实验结果表明,直接斜率波前复原算法将导致控制效果下降。 相似文献
63.
A comprehensive study of P, As, and hybrid As/P nLDD junctions is presented in terms of performance, reliability, and manufacturability for the first time. It is found that As junctions limit the performance of deep submicron devices due to unacceptable hot-carrier reliability, whereas a hybrid junction (light dose P added to medium dose As) dramatically improves hot-carrier reliability while maintaining high performance and manufacturability. For Leff of 0.19 μm, using this hybrid junction in a manufacturing process, an inverter gate delay of 32 ps, dc hot carrier life time exceeding ten years, and off-state leakage below 30 pA/μm at 2.9 V have been achieved 相似文献
64.
65.
The PBD-Closure of Constant-Composition Codes 总被引:3,自引:0,他引:3
Yeow Meng Chee Ling A.C.H. San Ling Hao Shen 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(8):2685-2692
We show an interesting pairwise balanced design (PBD)-closure result for the set of lengths of constant-composition codes whose distance and size meet certain conditions. A consequence of this PBD-closure result is that the size of optimal constant-composition codes can be determined for infinite families of parameter sets from just a single example of an optimal code. As an application, the sizes of several infinite families of optimal constant-composition codes are derived. In particular, the problem of determining the size of optimal constant-composition codes having distance four and weight three is solved for all lengths sufficiently large. This problem was previously unresolved for odd lengths, except for lengths seven and eleven. 相似文献
66.
Based on a polynomial operator approach, a new sparse controller structure is derived, which is actually an improved version of the recently proposed structure [Li, G. (2004). A polynomial-operator-based DFIIt structure for IIR filters. IEEE Transactions on Circuits and Systems II, 51, 147-151]. The performance of the proposed structure is analyzed by deriving the corresponding expression of roundoff noise gain and the problem of finding optimized sparse structures is solved efficiently with a genetic algorithm (GA). A numerical example is given, which shows that the newly developed structure can achieve much better performance than some well-known structures and particularly outperforms the traditional optimal fully parametrized realization greatly in terms of reducing roundoff noise and implementation complexity. 相似文献
67.
The possible hypocholesterolaemic properties of milk and fermented milk products have been investigated in groups of albino rats given a basal diet, basal diet plus cholesterol, and basal diet plus cholesterol together with whole milk or standard or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey or lactose-hydrolysed condensed whey. After 30 d, triacylglycerols, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol. In general, yogurts changed HDL-cholesterol little, but tended to raise triacylglycerols. There was marked lowering of LDL-cholesterol in rats given either type of yogurt fortified with whey proteins. This study has demonstrated in a rat model that bifidus yogurts and yogurts fortified with whey proteins can reduce total and LDL-cholesterol, and suggests that if they have the same effect in human subjects they have potential value in cholesterol-lowering diets. 相似文献
68.
Ilexonin A, a new drug in improving the blood circulation and microcirculation, is extracted from Ilicis pubescentis. The preventive and therapeutic effects of Ilexonin A on chemical salpingitis induced tubal obstruction (CSTO) with morphological and hemorheological change in rats was studied. Results showed that Ilexonin A was effective in treating (CSTO by oppositing the degeneration and necrosis of epithelium, inhibiting the hyperplasia of connective tissue, and reducing the infiltration of inflammatory cells. The improvement of morphology was more significant in treated groups than that in controls (P < 0.05-0.01). The indices concerning model rat's hemorheology were also analysed between treated groups and controls. It indicated that Ilexonin A could improve the viscosity of blood and aggregation of red blood cells. It is suggested Ilexonin A could promote the absorption of inflammatory substances as a result of improving hemorheology. 相似文献
69.
首先建立缺陷空间分布和粒径分布的模型,并讨论了缺陷通过版图产生电路错误的过程,给出了IC功能成品率模拟器XD-YES的实现。用XD-YES对微电子测试图和实际IC的功能成品率模拟和分析表明,其结果与实际符合很好,从而表明XD-YES的可行性和实用性。 相似文献
70.
It has been shown that coherent optical fiber receivers with a two-filter structure (TFS) consisting of a wide-band IF filter and a narrow-band postdetection filter are less susceptible to the influence of phase noise. However, the expanded IF bandwidth required to achieve optimum sensitivity performance is large, particularly in multichannel FSK systems. Forward error control coding can relax the laser linewidth requirement and improve receiver sensitivity. In this paper a multichannel asynchronous FSK scheme equipped with (31, k) Reed-Solomon codes is used to verify the coding benefit. A systematic error probability analysis is developed and a stable and accurate performance evaluation procedure is provided. The sensitivity penalties due to the combined phase noise and interchannel crosstalk for both coded and uncoded systems are calculated for comparison. The results show that the performance reduction due to phase noise can be largely alleviated by choosing a proper code rate and an optimum value of the expanded IF bandwidth 相似文献