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In this paper, the shielding performance of reinforced concrete construction is analyzed emplying the method of moment and equivalent principle. The surface of the reinforced concrete are modeled using rectangular surfaces patches. The surface of the reinforced concrete is assumed as metallized and modeled based on the equivalent principle. And the proposed technique has fewer unknown variables than...
In recent years, wearable devices such as smartphones are widely used. However, in real environment wearable devices are used, ESD occurrence conditions are considered to be different from previous test methods because wearable devices are usually held by users in their body. In this study, we measured electrical stress induced by ESD from a charged human's fingertip to grounded objects on wearable...
HEMP couplings characteristics for typical aircraft antenna are researched by experiment method. Firstly, the field uniformity and accuracy of experimental simulator are verified by numerical and experiment method. Then, the responses of monopole antenna, dipole antenna, blade antenna, GPS antenna under HEMP radiation environment are measured respectively. The measurement results are analyzed by the...
An analysis of frequency selective surfaces (FSSs) with high power handling capability is presented in this paper. Maximum field enhancement factor (MFEF) is applied to quantify the power handling capability of FSSs. The effects of various design parameters on the MFEF and frequency response of FSSs are investigated using split finite-difference time-domain (split-FDTD) method. It is observed that...
Generally speaking, the intersection point between the ray and the terrain can be judged in the simulation software adopting the method of ray tracing, and then where the ray is intersected, reflected or diffracted with the specific terrain can be judged. At present, most terrains are simulated in the form of triangular facet, while the judgment process for one time of intersection between one ray...
A non-hydrostatic mesoscale model Meso-NH is used to investigate the temporal evolution of thunderstorm charge structures. The thunderstorm happened on Nanjing of China. The used parameterizations of non-inductive charging was SAP98. Idealized cloud case was simulated here. The results indicate that the magnitude of the charges was increased and the height of location was lifted with the development...
This paper tries to estimate the absorption coefficient of the lightning coaxial unification fractal model (CUFM) from the particle point of view. Firstly, the lightning channel ionization and dissociation transitions have been studied. Secondly, by the Braginskii formula and the velocity current fractal relationship, the object function of the kappa coefficient and core radius is established. Finally,...
Numerical simulation method is a simple but effective method in the study of the damage behavior of carbon fiber reinforced polymer (CFRP) caused by lightning strike. A method to evaluate the internal damage area of CFRP is developed in this paper by superposing the temperature field of each layer, and damage effects of two kinds of CFRPs caused by different types of lightning currents are investigated...
As the emphasis on lightning protection for launch vehicle s, lightning indirect effects had taken into concern in nowadays. Among all the indirect effects action forms, the LEMP field radiation effect is one of the most common one. On the purpose of analyze the radiation effect on launch vehicles, a small launch vehicle model was established. Besides, a vertical LEMP field and a horizontal LEMP field...
The reasons for the electromagnetic interference of the intelligent pole mounted switch controller were analyzed and its sources of electromagnetic interference were classified. Secondly, some common electromagnetic interference issues were introduced and intelligent controller EMC design principles were proposed from the circuit design, PCB board layout and routing aspect. Finally, testing principle...
In this paper we summarize the initial results from a study of recent geomagnetic sudden storm commencement events, which typically represent the beginning of a geomagnetic storm as it arrives at the Earth. These are of interest because of possible adverse geomagnetic storm effects on power transmission lines in a power grid at all latitudes.
Magnetic shielding is an effective means to reduce low-frequency magnetic fields emitted from power cables and busbars. However, shielding against unbalanced currents has not been addressed well. This paper introduces equivalent magnetic dipoles for discussing magnetic shielding under a monopole current source. It is found that shielding is achieved by the cancellation of magnetic fields from both...
Bulk current injection (BCI) research has been done to complicated cable with ferromagnetic shielding layer. The nonlinear effect of shields has been investigated experimentally based on the built test system. Pulse current with different values have been injected to test the characteristic of two types of shielded cables. Test result show the nonlinear characteristic of transfer impedance obviously...
The non-contact eddy current sensor was used spread in the inverter- motor driving system to measure the vibration and rotate speed of the motor. But the electromagnetic environment is very complex in the inverter driving system, the sensor output should be affected by the electromagnetic interference. According to the MIL-STD-461F RS101, the upper frequency of magnetic field sensitivity measurement...
The measurement uncertainty of the electro-optical E-field measurement system is analyzed and calculated in this paper. Firstly, by analyzing the measurement and calibration process, the mathematical model of the measurement system is proposed. Then the influence factors of the measuring result is listed and their individual uncertainties are calculated under some approximations and assumptions. Finally,...
In this Paper firstly, the CSE (Conducted Spurious Emission) problem induced by shielding can in smart mobile phone design is experimentally analyzed, and the feasible solution is found. Then, the elements of circuits, which can be influenced by shielding can in smart mobile phone are classified into two categories, and they are the components and the micro-strip line. At last, by method of CST simulation...
Smoke emission is an important means to generate quick and wide-range camouflage, in this paper, smoke effect sequence diagrams and effective shielding area were acquired, the formula of M-T was fitted which based on the model of spatial relation between single smoke equipment and detector. The digital image analysis method of dynamic testing of smoke shielding effect was constructed. The dynamic...
The switching transients of electrical and electronic equipment (such as high-voltage isolation switch or circuit breaker) can generate various types of harassment transient immunity. This paper takes the electrical fast burst (EFT/B) as an example to specifically introduce the uncertainty of which couples pulse composed by numerous electrical fast transient to the power port of electrical and electronic...
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