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81.
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   
82.
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   
83.
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   
84.
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   
85.
The electrochemical properties of an electrochemical double-layer capacitor electrode based on an ultra-long (500 μm), aligned, carbon nanotube array (ACNTA) in Et4NPF6/propylene carbonate electrolyte are examined. The specific capacitance of the ACNTA electrode in an organic electrolyte is 24.5 F g−1, which is larger than that obtained in an aqueous electrolyte. The results of ac impedance measurements show that the ACNTA electrode gives a high power density and an excellent rate capability in an organic electrolyte. It is shown that the ACNTA electrode has a lower equivalent series resistance and a better rate capability than activated carbon electrode. This is due to the fact that ACNTA possesses a larger pore size and a more a regular pore structure. Both these features are conformed by scanning electron microscopic and nitrogen gas adsorption studies.  相似文献   
86.
矫直辊与板材的接触点位置对矫直过程影响的研究   总被引:1,自引:0,他引:1  
介绍了辊式矫直过程中,板材与矫直辊的接触点位置对矫直过程的影响,以及接触点对矫直过程影响的一系列研究,最后对接触点在矫直过程中的分析方法及作用进行了预测。  相似文献   
87.
针对750m^3高炉铁水生产富余状况,制订了富余铁水向铸铁机铸铁的调送方案,通过创新思维、系统挖潜、优化资源配置等措施的实施,保证了750m^3高炉的正常生产,取得了良好效果。  相似文献   
88.
Efficient encoding of IEEE 802.11n LDPC codes   总被引:1,自引:0,他引:1  
Cai  Z. Hao  J. Tan  P.H. Sun  S. Chin  P.S. 《Electronics letters》2006,42(25):1471-1472
Addressed is the issue of LDPC coding for the emerging IEEE 802.11n standard. An efficient encoding algorithm is proposed. The algorithm is simple and easy to implement. The memory requirement is trivial  相似文献   
89.
90.
High-quality, high-temperature superconducting (HTS) thin-films exhibit very low losses at microwave frequencies and, as a result, allow very high Q resonators to be produced. The size of such resonators may be significantly reduced by loading with low-loss single crystal dielectric. The potential for HTS dielectric loaded resonators as practical frequency standards and reference elements for low-phase-noise oscillators is assessed, with emphasis on operation at 60 K, a temperature readily attainable with compact Stirling cycle coolers  相似文献   
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