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This short monograph presents the theory of electromagnetic pulses in a simple and physical way. All pulses discussed are exact localized solutions of the Maxwell equations, and have finite energy, momentum and angular momentum.

Volcanic eruptions, as a natural phenomenon, can generate electric field disturbances that may interfere with the ionosphere, potentially impacting communication systems and electronic devices. This paper conducts identification and classification analyses of the electromagnetic pulse (EMP) disturbances in the very low frequency (VLF) electric field data observed by the China Seismo-Electromagnetic Satellite (CSES) and finds that volcanic eruption events can trigger EMP sequences. This paper first applies Fourier transform to the VLF electric field waveform data to convert it into 4 s spectrograms. Then, a series of operations such as grayscale conversion, edge feature enhancement, and binarization are performed on the spectrograms. Subsequently, a K-means clustering algorithm is applied to the binarized results to identify EMP events on the spectrograms. Finally, a classification analysis is performed on the identified results, revealing that multiple volcanic eruption events generate EMP sequences. The results of this paper not only provide new insights into the impact of volcanic eruptions on the electromagnetic environment but also have significant implications for enhancing the anti-interference capability of communication systems and optimizing electromagnetic environment monitoring technologies.

Electromagnetic pulse welding (EMPW) utilizing a magnetic field shaper for dissimilar sheet metals is a newly developed and high promising welding technology. Currently, there is a lack of research on this welding process concerning the plastic deformation of the workpiece and formation of metallurgical interfaces. To solve this, this paper initially employs the finite element simulation method to simulate the electromagnetic and structural fields, elaborating on the macroscopic and microscopic plastic deformations, as well as the local temperature variations in the workpiece under the action of electromagnetic forces during welding. Subsequently, welding experiments were carried out using 1 mm thick 1060 aluminum plates and 316 stainless steel plates. A microscopic examination of the welding interface was then performed, revealing that the numerical calculations align with the experimental outcomes.

Microstructure models are developed to computationally analyze the interactions between the constituents in heterogeneous materials and electromagnetic pulses (EMP). The models are used to explicitly simulate the material breakdown process by tracking the transition of dielectric constituents from non-conductive to conductive states. The focus is on the electric fields induced in the materials and the conditions for dielectric breakdown (defined as the onset of avalanche) caused by an artificially induced EMP excitation. The materials analyzed contain different combinations of dielectric and conductive constituents, a material made of cellulose-based KRAFT paper and mineral oil, PEEK 450G, and a gasket material (Parker Chomerics 1287). It is found that the electric field levels in the materials and the breakdown behavior are significantly affected by microstructure heterogeneities. The breakdown strengths of these materials depend on the microstructures, the dielectric constants, breakdown strengths, and the post-breakdown conductivity of the constituents. Graphical abstract

A problem of nonstationary diffraction of a monopolar TM-polarized electromagnetic pulse with a flat front on a thin slit in a perfectly conducting screen has been considered. The computational experiment techniques have been used to show that if the slit width is much smaller than the spatial length of a pulse, then a field is formed behind the screen in the form of a cylindrical monopolar pulse, i.e., there is a transformation of the shape of the incident field front without changing its pattern (monopolarity).

The term electromagnetic pulse (EMP) generally refers to high-power electromagnetic waves and can be classified into EMPs caused by nuclear weapons, non-nuclear EMPs, and EMPs caused by natural phenomena. EMPs can cause catastrophic damage to any electronic device consisting of electromagnetic components, including communications devices and transportation. In this study, the shielding effectiveness of paint was evaluated depending on the type and content of carbon material and binder. To analyze the compatibility and dispersibility improvement of the raw materials used in paint manufacturing, experiments were conducted in two stages, using 27 mixtures. The shielding effectiveness was evaluated for the optimal mixture developed through mixture experiments. The results of this study confirmed that the developed EMP shielding paint can improve the shielding effectiveness of concrete by 25–40 dB. Additionally, the adhesion strength and moisture resistance evaluation of the EMP shielding paint were evaluated. The average adhesive strength of the EMP shielding paint was 1.26 MPa. In moisture-resistance testing at a temperature of 50 ± 3 °C and a relative humidity of 95% or higher for more than 120 h, no cracks or peeling were observed on the painted surface.

Impact peril for warm-blooded organisms produced by a sequence of ultra-wideband electromagnetic sub-nanosecond pulses, used in various scientific and technological applications, is assessed by calculation methods of radiophysics and classical mechanics. Threshold values of the sequence parameters whose long time excess can be perilous for human have been determined.

This paper explores the use of a solid state transformer (SST) to mitigate the E3A component of a high-altitude electromagnetic pulse (HEMP) insult using external energy storage optimal control techniques. In lieu of conventional passive blocking devices or feedback-controlled energy storage devices, a novel implementation of Hamiltonian error tracking is utilized to develop a feedback control law for the variable converter ratio in an SST. The findings of the simulations performed in this paper suggest that additional energy storage is not necessary to protect an individual load from a HEMP insult. The simulations performed examine the response of a single-phase SST connected to a single voltage source on a long transmission line on the one side and a single linear resistor on the other. The control law is specifically developed for the late-time, low-frequency portion of a HEMP insult, namely the E3A components. The Hamiltonian error-based converter ratio control law is compared with nonlinear optimal feedforward controls to show that the HSSPFC is an external energy storage optimal controller.

The camera is a core device for modern surveillance and data collection, widely used in various fields including security, transportation, and healthcare. However, their widespread deployment has proportionally escalated associated security risks. This paper initially examines the current state of research on attack methods targeting camera systems, providing a comprehensive review of various attack techniques and their security implications. Subsequently, we focus on a specific attack method against universal serial bus (USB) cameras, known as electromagnetic pulse (EMP) attacks, which utilize EMP to prevent the system from detecting the cameras. We simulated EMP attacks using a solar insecticidal lamp (which generates EMP by releasing high-voltage pulses) and a commercially available EMP generator. The performance of the cameras under various conditions was evaluated by adjusting the number of filtering magnetic rings on the USB cable and the distance between the camera and the interference source. The results demonstrate that some USB cameras are vulnerable to EMP attacks. Although EMP attacks might not invariably cause image distortion or permanent damage, their covert nature can lead to false detection of system failures, data security, and system maintenance. Based on these findings, it is recommended to determine the optimal number of shielding rings for cameras or their safe distance from EMP sources through the experimental approach outlined in this study, thereby enhancing the security and resilience of USB camera enabled systems in specific scenarios.

This paper deals with an optimal operation method for surge protective devices (SPDs) to calculate the maximum continuous operating voltage (UC) and the voltage protection level (UP) by considering the sum of the voltage protection level and the dielectric continuous voltage limit of surge protective devices in order to effectively protect energy storage system (ESS) from switching and lightning surges. This paper also implements a test device for SPDs in ESSs based on the concept of a lightning electromagnetic surge protection measurement system (LPMS) by combining an SPD coordinated with spatial shielding with an ESS configuration. Here, the test device for the SPD in the ESS is composed of a power distribution unit (PDU), uninterruptible power supply (UPS), and a lightning electromagnetic pulse (LEMP) protection device, which combines two units of SPDs and disconnection switches (DSs) connected in parallel with two units of main circuit breakers (MCBs) and noise cut transformers (NCTs) connected in series. From the test results based on the proposed optimal operation method and test device, it is clear that the residual voltage with a third-class combination waveform can be kept within 1.5 kV of the surge voltage limit in all test scenarios, and it is confirmed that the proposed test device for SPDs can protect ESSs from switching and lightning surges. Therefore, it is confirmed that the SPD tested using the proposed method can effectively reduce switching and lightning surges, while the existing SPDs installed in ESS sites cannot protect ESSs from such surges.