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1.
Wireless Personal Communications - Recently, the theory of effective rate has attracted much attention, since it can take the delay aspect into account when performing channel capacity analysis. In...  相似文献   
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Neural Processing Letters - Part of Speech (POS) tagging is a sequential labelling task and one of the core applications of Natural Language Processing. It has been a challenging problem for the...  相似文献   
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In the recent sub-20 nm technology node, the process variability issues have become a major problem for scaling of MOS devices. We present a design for a strained Si/SiGe FinFET on an insulator using a 3D TCAD simulator. The impact of metal gate work function variability (WFV) on electrical parameters is studied. Such impact of WFV for different mole fractions (x) of the SiGe layer in a strained SOI-FinFET with varying grain size is presented. The results show that as the mole fraction is increased, the variability in threshold voltage (σVT) and off current (σIoff) is decreased; while, the variability of on-current (σIon) is increased. A notable observation is the distribution of electrical parameters approaches a normal distribution for smaller grain sizes.  相似文献   
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Analytical model for the transconductance, cut off frequency, transit time and fringing capacitance of LDD MOSFETs is presented with a simple approach. The analysis is carried out considering the LDD device as a conventional MOSFET with a series resistance [Z.-H. Liu et al., Threshold voltage model for submicrometer MOSFETs. IEEE Trans Electron Devices 1993; ED-40: 86–94] and a simple closed form expressions for cut off frequency and transit time is obtained. The total gate capacitance, i.e. the geometric and fringing capacitance, is calculated for both LDD and non-LDD devices and lower fringing capacitance is reported in LDD devices. Lower cut-off frequencies and higher transit time are reported in LDD devices for the same channel length.  相似文献   
6.
17-4 PH stainless steel is used as internal drive shaft material in liquid engine pumps. One of the drive shafts failed during operation. The shaft pieces were in contact for short duration after failure, which has resulted in abrasion of fractured surfaces. Samples from the location of failure were taken, and investigation of the failure was carried out using optical and scanning electron microscopy. The microstructural analysis of the material and fractographic analysis of the fractured surface show that the failure was caused by excessive torsion.  相似文献   
7.
During the early development of skeletal muscle, cardiac isotypes of several contractile proteins are known to be transiently expressed. We report here that skeletal muscle developing in vivo, as well as primary cultures derived from skeletal muscle, express mRNA encoding the cardiac dihydropyridine-sensitive calcium channel. The mRNA is detectable at high concentration at the earliest stage tested in vivo and diminishes rapidly in concentration as myofibers mature. The concentration of the cardiac calcium channel mRNA also diminishes during the in vivo development of skeletal muscle in a genetically paralyzed mouse (mdg), indicating that muscle contractile activity is not necessary for the down-regulation. In contrast, mRNA for the skeletal muscle-specific calcium channel accumulates gradually in developing skeletal muscle. A similar temporal pattern of expression is also seen in primary cultures of skeletal myotubes. These results raise the question of whether the cardiac calcium channel may be functionally important during the early development of skeletal myofibers.  相似文献   
8.
Electrochemical impedance measurements have been used to characterize zinc selenide films prepared by electrochemical co-deposition at a platinum rotating disk electrode. Estimations of capacitance and polarization resistance of variously prepared electrodeposits have been carried out to determine charge carrier density and corrosion rates.  相似文献   
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1,3,5‐Triglyceratetriazine [first tier (G1)] and tri(1,3,5‐triglycerate) triazine [second tier (G2)] dendrimers were prepared with 1,3,5‐trichlorotriazine and sodium glycerate in a 1 : 3 mass ratio in an ethanolic medium.G1 and G2 were amorphous, white, solid substances. Their structures were elucidated with IR, 1H‐NMR, and 13C‐NMR, and their thermal stability was studied with thermogravimetric analysis. The activation energy was calculated with the Freeman–Carroll model. Densities, viscosities, and surface tensions for 0.01–0.08 mol/kg aqueous solutions increased at 0.01 mol/kg for sodium glycerate, 1,3,5‐trichlorotriazine, 1,3,5‐triazine triglycerate chloride, G1, and G2. These values were measured at 298.15 K. The apparent molal volume, reduced viscosity, and inherent viscosity were calculated from the densities and viscosities, respectively. The data were regressed for the limiting densities, limiting apparent molal volumes, intrinsic viscosities, limiting inherent viscosities, and limiting surface tensions for solute–solvent interactions. The positive limiting apparent molal volume values were noted in the order of G2 > 1,3,5‐triazine triglycerate chloride > G1 > 1,3,5‐trichlorotriazine > sodium glycerate, with weaker hydrophilic intermolecular interactions of G2. The higher intrinsic viscosity and limiting inherent viscosity values for G2 implied stronger G2–H2O hydrophilic interactions, and the higher limiting apparent molal volume of G2 indicated slightly higher dynamic conformational changes in comparison with G1, with stronger structural activities. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
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