Effects Of Quality Factors Research Articles

Effect of Center Frequency Deviation in Miniaturized CMOS Bandpass Filter

In this letter, the effect of quality factor on center frequency deviation in miniaturized coupled line bandpass filter (BPF) with diagonally end-shorted at their opposite sides and lumped capacitors is theoretically analyzed. The miniaturized BPF of a two-stage structure with two types of quality factors in standard CMOS process was designed and manufactured at 5.5 GHz. The die area of BPF was . The measured center frequency of BPF with a quality factor of 4.9 was deviated from 5.5 GHz to 4.7 GHz. The one with 14.8 was shifted to 5GHz. The theoretical and measured results validate that quality factor influences the center frequency shift of BPF.

The field dependence of magnetoelastic damping in magnetostrictive material and its application in the magnetic field sensing

The magnetoelastic damping in magnetostrictive material is investigated. It is noted that the quality factor （the inverse measure of damping） of giant magnetostrictive material Terfenol-D is strongly dependent on bias direct current （DC） magnetic field. Taking advantage of the DC field dependence of magnetoelastic damping in magnetostrictive material, a DC or quasistatic magnetic sensor is proposed. The sensor is designed as a composite piezoelectric transformer （CPT） which is fabricated by bonding magnetostrictive material and piezoelectric transformer in layers. Theoretical analysis shows that the output voltage of the CPT is directly proportional to the quality factor of the CPT. Therefore, the output voltage of the CPT also strongly depends on DC field due to the strong field dependence effect of quality factor in magnetostrictive material. In addition, the ΔE effect of magnetostrictive material has little influence on the magnitude of the output voltage. A Terfenol-D/PZT8 composite transformer is fabricated for experiment. The experimental results show that the output sensitivity to DC field achieves ~5.12 mV·Oe-1 when the CPT is driven near resonance by an AC voltage with amplitude of 0.5 V.

Effect of quality factors especially of sweep of poplar trees on assortment structure

The factors of quality which affect the sawing yield were researched for poplar plantations, from the aspect of the application of national standards for roundwood. The research was performed in the period 2002-2003 on two temporary sample plots, in poplar plantations Populus?euramericana I-214 aged 25 years. The sample plots were selected depending on the clone species, planting pattern, and plantation flood risk, and branch pruning. The analyzed quality factors are: knots, minimal dimensions, sweep, false heart, ovality and tapering. The measured data were processed according to the original methodology. Based on the study results, the significance of quality factors was ranked in two different stand situations. Of all the study factors, knots have the highest effect on log yield, which is especially significant in marking for cross cutting of the larger trees. The sweep of trees in poplar plantations with higher flood risk is greater compared to the sweep of trees in plantations which are in the zone protected from floods. In poplar plantation Populus?euramericana I-214 which is exposed to frequents flooding (OP-2), sweep is the third significant factor, compared to the plantation protected from floods (OP?3), where sweep is the fifth factor according to significance. The effect of sweep in the plantation exposed to flooding is 2.4 times higher than the effect of sweep in the plantation protected from floods. Total value of the assortments made of tree trunk grows with the increase of tree diameter on both sample plots. This correlation is represented by the function Y=a?Xb, and the correlation between the variables is complete. The value of assortments of a certain quality for the study stand conditions can be calculated by the selected model functions, i.e. represented by assortment tables. This study shows inter alia, that there is not a unique model for all poplar plantations when the value percentage of assortments is determined, although they are homogeneous plantations by structural elements.