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101.
Navneet Rao 《电子设计应用》2007,(12):16-16,18,20,22,24,37
SRIO IP解决方案提供真实双向数据流,大大增强连接功能。目前,对高速通信与超快计算的需求正与日俱增。有线和无线通信标准的应用随处可见,数据处理架构每天都在扩展。较为普遍的有线通信方式是以太网(LAN、WAN和MAN网络)。手机通信是最为常见的无线通信方式,由应用了DSP的  相似文献   
102.
The chip-thickness models, used to assess the performance of grinding processes, play a major role in predicting the surface quality. In the present paper, an attempt has been made to develop a new chip-thickness model for the performance assessment of silicon carbide grinding by incorporating the modulus of elasticities of the grinding wheel and the workpiece in the existing basic chip-thickness model to account for elastic deformation. The new model has been validated by conducting experiments, taking the surface roughness as a parameter of evaluation .  相似文献   
103.
本文提出了适于三种序号的Chrestenson函数序列的复制方法,对其复制过程进行了数学分析,并指出当Chrestenson函数退化为Walsh函数时,此方法即为复制理论中的平移复制方法。  相似文献   
104.
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106.
Optimal operation of a multibasin reservoir system   总被引:1,自引:0,他引:1  
A simulation-optimization procedure is presented for evaluating the extent of interbasin transfer of water in the Peninsular Indian river system consisting of 15 reservoirs on four river basins. A system-dependent simulation model is developed incorporating the concept of reservoir zoning to facilitate releases and transfers. The simulation model generates a larger number of solutions which are then screened by the optimization model. The Box complex nonlinear programming algorithm is used for the optimization. The performance of the system is evaluated through simulation with the optimal reservoir zones with respect to four indices, reliability, resiliency, vulnerability and deficit ratio. The results indicate that by operating the system of 15 reservoirs as a single unit the existing utilization of water may be increased significantly.  相似文献   
107.
Xylose reductase (XR) from Neurospora crassa was purified to homogeneity and was found to be specific to NADPH (nicotinamide adenine dinucleotide phosphate). The purified enzyme showed M(r) of 60 and 29 kDa by gel filtration and SDS-PAGE indicating the presence of two subunits. The kinetic mechanism of xylose reductase is 'iso-ordered bi bi'. Inactivation of XR by N-bromosuccinimide (NBS) was found to be biphasic with second-order rate constants of 2.5 x 10(2) and 80 M-1S-1 for the fast (kf) and slow phase (ks), respectively. NADPH protected 90% of XR activity against inhibition by NBS. The fluorescence and circular dichroism (CD) studies revealed that inactivation was not due to gross conformational change in the enzyme. Analysis of the modified Stern-Volmer plot indicated that 49% of the tryptophanyl fluorescence was available for quenching which was completely abolished in the presence of NADPH confirming the involvement of tryptophan at the coenzyme binding site. Experimental evidence presented here serves to implicate the involvement of a tryptophan residue at the low-affinity NADPH binding site and the nature of this site has been assessed by using the hydrophobic probe ANS.  相似文献   
108.
109.
The occurrence of a significant amount of age hardening, due to the precipitation of the γ′ phase, has been demonstrated in the nickel-copper base alloy MONEL K 500. The microstructure of the precipitation-hardened and deformed alloy has been examined in peak-aged underaged and overaged conditions. An attempt has been made to compare the observed increments in strength in these three aged conditions to those predicted on the basis of relevant theoretical models.  相似文献   
110.
Pseudobinary alloy, Tb0·27Dy0·73Fe2−δ , belonging to C-15 cubic Laves phase having MgCu2-type structure, possesses large magnetostriction and high magnetomechanical coupling coefficient. The advantages of this material over existing piezoelectric materials, particularly for SONAR applications, are highlighted. Recent results on the influence of cobalt (Co) on magnetic and magnetomechanical properties of Tb0·27Dy0·73Fe2 are discussed.  相似文献   
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