电磁场

To solve the problem, a concept of dynamic antenna is introduced, which comprises the antenna with wireless sensor, wheels, and vehicle body. A 3D electromagnetic simulation model for the dynamic antenna is built and a simulation is performed. The parameters of dynamic antenna obtained by the simulation are then used in the design of matching circuit of base antenna.

针对该问题提出将无线传感器天线、轮毂、车身看作一个动态天线，建立动态天线的三维电磁场仿真模型，并将仿真得到的动态天线参数用于无线传感器天线的匹配电路设计。

The performance of switch and antenna are obtained by HFSS software simulation, respectively.

利用三维电磁场软件HFSS分析了设计结构，包括开关、天线，在0～10 GHz得出开关性能插入损耗在-1dB以下，天线回波损耗在-26dB以下。

Two energy level atom is the ideal model of the actual atom, it only has two non-degeneration energy levels, E and E .

相干态光场是与经典电磁场最为接近的量子态光场，它是研究激光最重要的理论工具。

The results show that at close distances, the field waveform is dependent strongly on azimuth; at distance of several hundreds, the ratio of the peak error values at two azimuths may be bigger than 2; at the distance of 1 km, the mean error is less than 10% with a maximum value of 50%.

结果表明，回击电磁场随方位角的变化非常明显，在距闪电通道几百米距离，误差可达2倍；在1 km处，闪电通道的垂直假定对时域回击辐射场峰值计算的相对误差最大为50%左右，平均小于10%。

For interior problems, an electromagnetic field propagates or oscillates in a closed structure such as an accelerator chamber, a microwave filter, or a high-speed electronic package.

为内部问题，一个电磁场传播或振荡在一个封闭的结构里，比如加速器室、微波滤波器、高速电子晶体管。

Al-Zn-Mg-Cu-Zr aluminum alloys were prepared by electromagnetic casting and direct chill casting, respectively. The effects of electromagnetic field on as-cast microstructure and alloy elements solid solubility inside crystals of Al-Zn-Mg-Cu-Zr aluminum alloy were investigated.

摘 要：分别采用电磁铸造和普通连铸技术制备Al-Zn-Mg-Cu-Zr合金，研究电磁场对合金显微组织、合金元素晶内固溶度的影响。

Al-Zn-Mg-Cu-Zr aluminum alloys were prepared by electromagnetic casting and direct chill casting, respectively. The effects of electromagnetic field on as-cast microstructure and alloy elements solid solubility inside crystals of Al-Zn-Mg-Cu-Zr aluminum alloy were investigated.

分别采用电磁铸造和普通连铸技术制备Al-Zn-Mg-Cu-Zr合金，研究电磁场对合金显微组织、合金元素晶内固溶度的影响。

Physical model of computer box is established and through analyzing the changing curves of change of electromagnetic field with time and change of coupling coefficient with frequency, the coupling regulation of electromagnetic on computer box is obtained. It is as follows: electromagnetic pulse has a great effect on components of computer box through apertures and slots, the coupling energy in the box increases first and then decreases. The existence of components decreases the shielding effectiveness and resonant frequency.

建立计算机机箱的物理模型，通过分析机箱内的电磁场随时间的变化曲线和耦合系数随频率的变化曲线，得到电磁脉冲对计算机机箱的耦合规律：电磁脉冲可以通过孔缝进入机箱内部，对机箱内元件的瞬间影响较大；机箱内的耦合能量是先增加后减小；元件的存在使得机箱的屏蔽效能降低，谐振频率下降。

In this paper, the theorical analysis and computer stimulate calculation have been used to research the reflection of electromagnetic wave of metal plane, metal cylinder and metal sphere, surface of which all have been covered by a plasma slab, and we draw some useful conclusion.

本论文采用理论分析和计算机模拟计算的方式，分别研究了平板，圆柱，和金属球在附有等离子体层的情况下，反射电磁场的变化，得到了一些有用的结论。

The whole-space response characteristics for three dimensional conductive body located in the floor of the mine drift either in homogeneous medium or in layered medium was simulated, with using Mur absorbing boundary condition and taking a electrical dipole source in homogeneous whole space as a initial source; the diffused regularity of the transient field in homogeneous medium at 1.9 μs and 27.6 μs,and in layered medium at 1.2 μs and 0.023 ms was discussed.

利用Mur吸收边界条件，选用均匀全空间电偶极源作为初始激发源，模拟了均匀介质中巷道底板岩层内部和层状介质中三维低阻异常体的全空间响应特性，分析了瞬变电磁场在均匀介质中1.9 μs和27.6 μs两时刻的传播规律及在层状介质中1.2 μs和0.023 ms两时刻的传播规律。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。