阻抗比

The method of moments is used to analyze and calculate the broadband characters of impedance,voltage satanding wave ratio,gain and radiation pattern of larger angle LPDA,and the relation between these characters and the parameter of antenna construction is discussed in this paper.

本文采用矩量法分析和计算了对数周期天线在张角较大时，它的阻抗、电压驻波比、增益及方向图的宽带特性，讨论了这些特性与天线结构参数之间的关系。

The broadband transmission-line transformer with 4:1 impedance transformation ratio is studied,its equivalent model with mutual coupling between transmission-lines is given,and its impedance transformation characteristics are analyzed.

研究了变换比为4：1的宽频带传输线变压器，给出了考虑线圈互耦的等效电路模型，分析了其阻抗变换特性。

Finally, determine reservoir lithology and pore fluid properties. This method requires only small and medium angle seismic data, and all other elastic parameters are from the elastic density ratio and acoustic impedance.

该方法仅需要近、中角度的地震数据，其他弹性属性参数是由弹性密度比与声波阻抗之间的关系通过道运算获得，提高了计算效率，可用于绝大多数采集条件下获得的地震数据叠前反演。

The electric characteristic parameters of this novel sleeve antenna are calculated, including the input impedance, voltage standing wave ratio, horizontal gain and radiation pattern.

研究了这种新型套筒天线的输入阻抗、电压驻波比、增益及辐射方向图等电特性。

A small size MMW CP microstrip antenna is designed using sequential phase rotation method in this paper.The simulation result shows that this antenna has wider impedance bandwidth and axial ratio bandwidth.

采用连续相位旋转法设计了一种四单元的小尺寸的毫米波圆极化微带天线阵列，仿真表明：该天线具有较宽的阻抗带宽和轴比带宽。

Sections such as P- and S-wave impedance, velocity ratio of P- and S-wave,λρ, and μρ, as well as crossplotting sections of different lithological parameters were generated.

利用这些成果，可以得到比常规波阻抗反演更准确、更丰富的储层信息，在目标储层的含气性识别中取得了很好地效果。

For a constant impedance load or a constant current load, if regulating the secondary voltage by making the changer ratio higher, the primary voltage will get much lower while the load power is restoring, and the power will then lose balance. For a constant power load or a motor load, since the change of OLTC has no or little influence on the load power, the voltage of primary side almost has no change whether the tap operates or not. The influence on the voltage stability with respect to the dynamic restoring load which is sensitive to voltage is also discussed.

对于恒阻抗和恒电流型负荷，在变比上调恢复副边电压的情况下，负荷功率恢复，又使原边电压下降，可使系统功率失去平衡，而对于恒功率负荷和电动机负荷，OLTC的变化不会引起负荷功率的恢复，OLTC的变化对系统电压稳定有利；同时研究了对于一般电压敏感和具有动态恢复特性的负荷，反调分接头对电压稳定性的影响。

The real data verification shows that the wavelet, reflection factor and acoustic impedance given by PCGA are more accurate, quicker convergent and value stable than the existing direct sparse inversion method.

用实际数据检验算法，表明预条件共轭梯度法反演的子波、反射系数和波阻抗要比直接稀疏反演精度高、收敛快、数值稳定。

AC impedance spectroscopy analysis indicated that the interface resistance and ohmic resistance of the latter were markedly less than that of the former.

通过交流阻抗谱分析，后者电池的欧姆电阻与界面电阻均比前者明显减小。

The results indicate that the cell only doped with Al2O3 (Cell 1) is of the worst output performance at 850 ℃, the output power density being 0. 083 W/cm^2, and that the cell doped with Al2O3 and coated with buffer layer (Cell 2) is of the best output performance at the same temperature, the output power density being 0.120W/cm^2. AC impedance spectroscopy analyses indicate that the interface resistance and Ohmic resistance of Cell 2 are obviously less than those of Cell 1, meaning that insulative nickel aluminum spine1 is generated by the reaction of Al2O3 and NiO during the sintering at a high temperature.

结果表明：850℃时，含Al2O3的电池输出性能最差，输出功率约为0.083 W/平方公分；含Al2O3并具有过渡层的电池输出性能最好，输出功率约为0.120 W/平方公分；交流阻抗谱分析表明，含Al2O3并具有过渡层的电池的欧姆电阻与界面电阻均比不含过渡层的明显减小，说明YSZ中添加的Al2O3在高温烧结过程中，与阳极材料NiO发生反应生成不导电的镍铝尖晶石。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。