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Journal articles on the topic 'Transient electromagnetic'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 June 2025

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1

Geronimi, C., F. Bouchut, M. R. Feix, H. Ghalila, M. Valentini, and J. M. Buzzi. "Transient electromagnetic field." European Journal of Physics 18, no. 2 (1997): 102–7. http://dx.doi.org/10.1088/0143-0807/18/2/009.

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2

Xia, Cheng Jun, Guo Kai Liang, and Hao Yu Huang. "An Investigation of the Negative Resistance in Network Reduction and Electromagnetic Transient Modelling." Advanced Materials Research 1008-1009 (August 2014): 480–84. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.480.

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It becomes common practice to reduce a large-scale power grid into a simplified one using transient stability simulator and have it modeled on electromagnetic transients programs. However, the procedure of network reduction may produce negative resistance, which may result in some problems in electromagnetic transient simulation. This paper firstly demonstrates that the negative resistance will probably lead to numerical instability in electromagnetic transient simulation. And then the forming mechanism of the negative resistance during network reduction using Gaussian Elimination is revealed. Several schemes for negative resistance elimination are presented at last.

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3

Guillén, Daniel, Gina Idárraga-Ospina, and Camilo Cortes. "A New Adaptive Mother Wavelet for Electromagnetic Transient Analysis." Journal of Electrical Engineering 67, no. 1 (2016): 48–55. http://dx.doi.org/10.1515/jee-2016-0007.

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Abstract Wavelet Transform (WT) is a powerful technique of signal processing, its applications in power systems have been increasing to evaluate power system conditions, such as faults, switching transients, power quality issues, among others. Electromagnetic transients in power systems are due to changes in the network configuration, producing non-periodic signals, which have to be identified to avoid power outages in normal operation or transient conditions. In this paper a methodology to develop a new adaptive mother wavelet for electromagnetic transient analysis is proposed. Classification is carried out with an innovative technique based on adaptive wavelets, where filter bank coefficients will be adapted until a discriminant criterion is optimized. Then, its corresponding filter coefficients will be used to get the new mother wavelet, named wavelet ET, which allowed to identify and to distinguish the high frequency information produced by different electromagnetic transients.

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4

Mollidor, L., B. Tezkan, R. Bergers, and J. Löhken. "Float-transient electromagnetic method: in-loop transient electromagnetic measurements on Lake Holzmaar, Germany." Geophysical Prospecting 61, no. 5 (2013): 1056–64. http://dx.doi.org/10.1111/1365-2478.12025.

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5

Tang, Fan, Guo Liang Su, Dong Xiang Li, and Yu Hong Wang. "Electromagnetic - Electromechanical Transient Hybrid Simulation of Deyang-Baoji HVDC System Based on ADPSS." Advanced Materials Research 805-806 (September 2013): 935–40. http://dx.doi.org/10.4028/www.scientific.net/amr.805-806.935.

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three kinds of digital programs used in power system simulation are summarized in this paper. The electromagnetic and electromechanical transient simulation software ADPSS is introduced. Electromagnetic transient simulation, electromechanical transient simulation and electromagnetic-electromechanical transient hybrid simulation are performed respectively on Deyang-Baoji ±500KV HVDC system. The simulation result shows that the electromagnetic-electromechanical transient hybrid simulation has the advantage of electromagnetic transient simulation and electromechanical transient simulation. It can effectively analyze the process of the local electromagnetic transient in large-scale grid. The simulation speed is fast and the result is accurate and reliable.

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6

QU Fang, 曲放, and 翁爱华 WENG Ai-hua. "Transient Electromagnetic Method and Application." OME Information 28, no. 12 (2011): 82–88. http://dx.doi.org/10.3788/omei20112812.0082.

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7

Wiggins, C. M., D. E. Thomas, F. S. Nickel, T. M. Salas, and S. E. Wright. "Transient electromagnetic interference in substations." IEEE Transactions on Power Delivery 9, no. 4 (1994): 1869–84. http://dx.doi.org/10.1109/61.329520.

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8

叶, 英. "Transient Electromagnetic Structure Radar Research." Advances in Geosciences 09, no. 04 (2019): 218–29. http://dx.doi.org/10.12677/ag.2019.94025.

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9

Adhidjaja, Jopie I., Gerald W. Hohmann, and Michael L. Oristaglio. "Two‐dimensional transient electromagnetic responses." GEOPHYSICS 50, no. 12 (1985): 2849–61. http://dx.doi.org/10.1190/1.1441904.

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The time‐domain electromagnetic (TEM) modeling method of Oristaglio and Hohmann is reformulated here in terms of the secondary field. This finite‐difference method gives a direct, explicit time‐domain solution for a two‐dimensional body in a conductive earth by advancing the field in time with DuFort‐Frankel time‐differencing. As a result, solving for the secondary field, defined as the difference between the total field and field of a half‐space, is not only more efficient but is also simpler and eliminates several problems inherent in the solution for the total field. For example, because the secondary field varies slowly both in space and time, it can be modeled on a coarse grid with large time steps. In addition, for a simple body the field is local; therefore, because the field can be assumed to satisfy a simple boundary condition in the earth computation is greatly simplified. Our tests show that for the same accuracy, the secondary‐field solution is roughly five times faster than the total‐field solution. We compute and analyze the magnetic field impulse response for a suite of models, most of which consist of a thin body embedded in a conductive half‐space—with or without overburden. The results indicate the conductive half‐space will both delay and attenuate the response of the body and even obscure it if the conductivity contrast is small. The results also suggest that the conductive host can alter the decay rate of the response of the body from its free‐space counterpart. Our results for multiple bodies illustrate the importance of early‐time measurements to obtain resolution, particularly for measurements of the horizontal magnetic field. The vertical magnetic field, however, can be used to infer the dip direction of a dipping body by studying the migration of the crossover. The results for models which include overburden show that the effect of a conductive overburden, in addition to the half‐space effect, is to delay the response of the body, because the primary current initially tends to concentrate and slowly diffuse through the overburden, and does not reach the body until later time. This effect also complicates the early‐times profiles, becoming more severe as the conductivity of the overburden is increased.

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10

Fitterman, David V., and Mark T. Stewart. "Transient electromagnetic sounding for groundwater." GEOPHYSICS 51, no. 4 (1986): 995–1005. http://dx.doi.org/10.1190/1.1442158.

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The feasibility of using the transient electromagnetic sounding (TS or TDEM) method for groundwater exploration can be studied by means of numerical models. As examples of its applicability to groundwater exploration, we study four groundwater exploration problems: (1) mapping of alluvial fill and gravel zones over bedrock; (2) mapping of sand and gravel lenses in till; (3) detection of salt or brackish water interfaces in freshwater aquifers; and (4) determination of hydrostratigraphy. These groundwater problems require determination of the depth to bedrock; location of resistive, high‐porosity zones associated with fresh water; determination of formation resistivity to assess water quality; and determination of lithology and geometry, respectively. The TS method is best suited for locating conductive targets, and has very good vertical resolution. Unlike other sounding techniques where the receiver‐transmitter array must be expanded to sound more deeply, the depth of investigation for the TS method is a function of the length of time the transient is recorded. Present equipment limitations require that exploration targets with resistivities of 50 Ω ⋅ m or more be at least 50 m deep to determine their resistivity. The maximum depth of exploration is controlled by the geoelectrical section and background electromagnetic (EM) noise. For a particular exploration problem, numerical studies are recommended to determine if the target is detectable.

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11

Peacock, J., and A. King. "Central loop transient electromagnetic soundings." Exploration Geophysics 16, no. 2-3 (1985): 261–65. http://dx.doi.org/10.1071/eg985261.

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12

Tang, Jun. "Application of Wavelet Analysis in Transient Electromagnetic Sounding." Advanced Materials Research 346 (September 2011): 757–63. http://dx.doi.org/10.4028/www.scientific.net/amr.346.757.

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On the basis of explaining the basis theory on transient electromagnetic sounding, wavelet theory and imaging principle of differential conductivity for transient electromagnetic sounding data, this thesis proposes rapid imaging technology of electromagnetic sounding based on wavelet analysis, describes the characteristics of noises under wavelet decomposition, and employs wavelet packet analysis to eliminate noise of signals, at last, introduces wavelet analysis into transient electromagnetic sounding on the platform of MATLAB wavelet function toolbox and deals with differential conductivity imaging processing steps of transient electromagnetic sounding.

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13

Kristensson, G. "Transient electromagnetic wave propagation in waveguides." Journal of Electromagnetic Waves and Applications 9, no. 5-6 (1995): 645–71. http://dx.doi.org/10.1163/156939395x00866.

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14

叶, 英. "Research on Transient Electromagnetic Road Radar." Advances in Geosciences 09, no. 06 (2019): 529–41. http://dx.doi.org/10.12677/ag.2019.96057.

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15

Harada, Koichiro, Kazushige Wada, and Masami Fukuda. "Permafrost mapping by transient electromagnetic method." Permafrost and Periglacial Processes 11, no. 1 (2000): 71–84. http://dx.doi.org/10.1002/(sici)1099-1530(200001/03)11:1<71::aid-ppp339>3.0.co;2-#.

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16

Zhdanov, M. S., M. A. Frenkel, and A. I. Katsevich. "Interpolation method for transient electromagnetic fields." Il Nuovo Cimento C 12, no. 5 (1989): 555–65. http://dx.doi.org/10.1007/bf02508015.

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17

Christensen, Niels B. "Sensitivity functions of transient electromagnetic methods." GEOPHYSICS 79, no. 4 (2014): E167—E182. http://dx.doi.org/10.1190/geo2013-0364.1.

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Any geophysical measurement is a filter through which the distribution of a certain physical parameter in the subsurface is seen, and the sensitivity function is a characteristic of the method that reveals the nature of this filter. Insight into the structural pattern of the sensitivity function pertaining to a certain transmitter-receiver configuration provides the geophysicist with an image that allows an immediate qualitative understanding of the characteristics of the method. The assets and shortcomings of different measuring configurations can be discussed and understood, and the sensitivity function permits qualified predictions about resolution characteristics of new configurations and measuring strategies. I evaluated a rapid and accurate method for calculating 3D sensitivity functions of a homogeneous half-space model for a wide variety of transient electromagnetic configurations using the central loop and an airborne offset loop configuration as examples. Computations of 3D sensitivity functions were performed as convolutions in the time domain between the electric fields from the transmitter and the receiver, had it been used as a transmitter. The 2D and 1D sensitivity functions are found through numerical integration of the 3D functions. Beside offering insight into the resolution capability of the measuring configuration, the sensitivity functions lend themselves to rapid calculations of approximate responses and derivatives in various modeling and inversion strategies.

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18

Wang, Guo Fu, Peng Deng, Fa Quan Zhang, and Jin Cai Ye. "Noise Reduction of the Transient Electromagnetic Weak Signal under Strong Noise Based on Power Detection of EMD." Applied Mechanics and Materials 110-116 (October 2011): 1606–12. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.1606.

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The method of Transient Electromagnetic(TEM) detection is widely applied to the field of coal mine and oil exploration. But since Transient Electromagnetic signal is a non-stationary , nonlinear , weak signal under the background of heavy noise , traditional method which is based on the signal superposition is only suited to the signal of the superficial layer , it can not fetch the weak signal of the deep layer. noise reduction of the transient electromagnetic weak signal under heavy noise based on power detection of EMD decomposition is presented in this paper. This method does not need prior information. Through the method, the transient electromagnetic weak signal under heavy noise is decomposed to several intrinsic mode functions. Then by power detection, the noise leading component is extracted and reduced .At last the transient electromagnetic weak signal is obtained adaptively. The example of this paper show: when the received TEM signal of deep layer is -30db SNR, This method can reduce the most of noise, obtain the transient electromagnetic weak signal which contains geological information, and improve the depth and accuracy of the TEM detection.

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19

Mezaroba, Marcello, Neomar Giacomini, and Raphael Jorge Millnitz dos Santos. "Fast Transient Generator For Electromagnetic Interference Tests." Eletrônica de Potência 14, no. 3 (2009): 211–19. http://dx.doi.org/10.18618/rep.2009.3.211219.

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20

Wang, Hong Ming, Bo Feng Yang, Bang Min Song, and Yi Nan Zhao. "Transient Simulation of Electromagnetic Field during EMCC Process." Applied Mechanics and Materials 66-68 (July 2011): 189–93. http://dx.doi.org/10.4028/www.scientific.net/amm.66-68.189.

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A transient analysis mathematic model was established via ANSYS. The variation laws of magnetic induction density, induced eddy current and electromagnetic force in molten steel changing with the high frequency sine exciting current were investigated. The results indicate that the magnetic induction density and induced eddy current in molten steel vary at the same frequency as exciting current. Moreover, the variations of magnetic induction density and induced eddy current are not in step with exciting current. This proves that the high frequency electromagnetic field in mold and steel is not a time-harmonic wave. The electromagnetic force varies at the double frequency of the exciting current. When the exciting current reaches the amplitude value, the electromagnetic force is close to the max value, whereas when the exciting current returns to zero, the electromagnetic force is not zero. At the same time, there is partial electromagnetic force reversing its direction. If the reversed electromagnetic force is expanded seriously, the fluctuation of liquid level is induced, so it must be controlled.

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21

Liu, Yaoning, Shucai Liu, Maofei Li, Xinming Liu, and Weihong Guo. "Influence of metal roadway supports on transient electromagnetic detection in mines." Earth Sciences Research Journal 25, no. 1 (2021): 109–14. http://dx.doi.org/10.15446/esrj.v25n1.80156.

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To study the influence of metal supports in roadways on the detection of mines using the transient electromagnetic method, authors treated metal supports including anchor nets as a thin metal layer. According to the finite differences principle, the characteristics of the full-space transient electromagnetic response under the thin metal layer’s influence were calculated using a non-uniform grid. The thin metal layer’s presence slowed the electromagnetic field’s diffusion rate and hindered the overall diffusion. The transient electromagnetic response curve observed under the thin metal layer’s influence was higher than that without the supports. Thicker metal layers resulted in higher early response values and slower decay rates. The decay rate increased as a function of time, gradually approaching that of the curve without metal supports. The simulation of the transient electromagnetic response to the model of water-containing low-resistance structures showed that the metal roadway support reduced the sensitivity of the transient electromagnetic method and weakened its response to low-resistance anomalies.

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22

Zhang, Lei, Qing Ming Duan, Hao Sun, et al. "Design of Transient Electromagnetic Transmitter Based on FPGA." Applied Mechanics and Materials 496-500 (January 2014): 630–33. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.630.

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Transient electromagnetic transmitter is a part of the transient electromagnetic detection system. In the aspect of short turn-off time for high-power current, there are still many problems to be solved urgently. This paper put forward a design scheme of transient electromagnetic transmitter, amplified the control signal with triode, and put forward a kind of passive constant voltage clamping absorbing circuit, which made the turn-off time shorter and the linearity of the emission currents lagging edge higher. This transient electromagnetic transmitter system is portable and easy to operate. Through experiments we can prove that the transmitter has the characteristic of short turn-off time and high reliability, and it has reached the requirements of field application.

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23

Dong, Hua Ying, Li Ze Xu, Gui Shu Liang, Xin Liu, and Xu Cheng. "Wide-Band Modeling of Grounding Grid Based on the Fractional Order Differential Theory." Advanced Materials Research 860-863 (December 2013): 2292–95. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.2292.

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Research on the wide-band modelling method of the grounding grid and the analysis of the electromagnetic transients on the grounding grid has significant practical meaning on the engineering problems, e.g. overvoltage protection, insulation coordination and electromagnetic interference and the increasing levels of capacity in the power and communication systems. This paper presents strategies which establish the equivalent circuit for computing the transient performance of grounding grid base on fractional order differential theory, which takes into account the fractional frequency characteristics of soil permittivity. In order to validate the presented method, an example is considered and the transient responses are compared with the results obtained by the method of moments.

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24

Zhou, Lei, LiangJun Yan, Osborne Kachaje, Xingbing Xie, Yurong Mao, and Haoran Zhang. "The Simulation of Transient Electromagnetic Based on Time-domain IP Model." Journal of Environmental and Engineering Geophysics 24, no. 1 (2019): 159–62. http://dx.doi.org/10.2113/jeeg24.1.159.

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When transient electromagnetic investigation methods are carried out in the field, the measured data often contain both the induced polarization (IP) effect and the electromagnetic effect. In order to study the IP effect in the transient electromagnetic response, many researchers first calculate the electromagnetic field which considers the IP effect by replacing traditional resistivity with complex resistivity of the Cole-Cole model in the frequency domain. After the forward modeling calculation of the electromagnetic field in the frequency domain that considers the IP effect, the transient electromagnetic field in time-domain is obtained by a time-frequency transform algorithm. In this paper, the resistivity is directly replaced by the time-variant resistivity expression of the Cole-Cole model by using digital filter algorithms when we simulate the transient electromagnetic fields in time- domain. The calculated result of the Cole-Cole model in time-domain and in frequency-domain are consistent with each other, as observed in the horizontal electric field and the vertical magnetic field comparisons, which indicates the correctness of the numerical computation method adopted in this paper. The research presented herein allows us to observe the influence of the IP effect on transient electromagnetic field as well as study the mechanisms of IP directly.

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25

Munkholm, Mette S., and Esben Auken. "Electromagnetic Noise Contamination on Transient Electromagnetic Soundings in Culturally Disturbed Environments." Journal of Environmental and Engineering Geophysics 1, no. 2 (1996): 119–27. http://dx.doi.org/10.4133/jeeg1.2.119.

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26

Qi, Zhipeng, Xiu Li, Yingying Zhang, He Li, and Naiquan Sun. "An Array Source TEM Apparent Resistivity Conversion and Differential Conductivity Imaging Method and its Potential Applications." Journal of Environmental and Engineering Geophysics 24, no. 4 (2019): 579–92. http://dx.doi.org/10.2113/jeeg24.04.579.

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In this study, for the purpose of accurately detecting fissured disaster sources and diversion channels during tunnel construction, an array source transient electromagnetic device is proposed. Then, an apparent resistance conversion method and an approximate inversion algorithm for the proposed transient electromagnetic device are presented. First, a finite-difference time-domain (FDTD) method is used for the forward modeling of the proposed array source transient electromagnetic device, and the electromagnetic responses of the cracks and water-conducting channels are obtained. When compared with the transient electromagnetic square responses of the traditional loop sources, it is found that the data confirmed that the responses to the anomalies of the proposed array source transient electromagnetic device are more apparent. Then, the transformation from the array source transient electromagnetic field to the apparent resistivity is realized according to the principle of inverse function. In order to clearly identify the boundaries of the targeted anomalous bodies, a multi-source S-inversion algorithm is used to realize the array source transient electromagnetic differential imaging. The method is validated using a theoretical model. It was determined that the results of the differential imaging had effectively identified the boundaries of the anomalous bodies, and the apparent resistivity imaging had successfully determined the resistivity distributions of the anomalous bodies. Furthermore, a combination of the aforementioned methods is used to effectively identify the faults and water-flowing fractures in the model. This study's proposed algorithm was applied to the actually measured data, and the interpretation results were found to be consistent with the excavation results, which fully demonstrated the feasibility of the proposed method.

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27

Bo, Yang, Wang Qian, Xu Zhengyu, and Bao Minghui. "Research on Transient Electromagnetic Detection Method for Substation Site Selection." E3S Web of Conferences 194 (2020): 03014. http://dx.doi.org/10.1051/e3sconf/202019403014.

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A transient electromagnetic detection method for site selection of substation grounding is proposed in this paper. And taking the fault detection experiment of transmission lines in a certain area of China as an example, the transient electromagnetic technology is used to obtain high-quality images reflecting the development trend and distribution of geological faults. The results show that the transient electromagnetic method is a convenient and effective way for substation site selection.

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28

Huang, Qiuhua, and Vijay Vittal. "Application of Electromagnetic Transient-Transient Stability Hybrid Simulation to FIDVR Study." IEEE Transactions on Power Systems 31, no. 4 (2016): 2634–46. http://dx.doi.org/10.1109/tpwrs.2015.2479588.

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29

Lefebvre, P. J., and W. W. Durgin. "A Transient Electromagnetic Flowmeter and Calibration Facility." Journal of Fluids Engineering 112, no. 1 (1990): 12–15. http://dx.doi.org/10.1115/1.2909360.

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An electromagnetic flowmeter was developed to measure transient flows at a data rate of 60 Hz. The approach taken was to develop suitable electronics to replace the electronics of a commercially available electromagnetic flowmeter normally used for steady-state operation. Use of the commercially available flowmeter body, which includes the magnetic coils, core, and signal electrodes, provided a relatively economical means of fabricating the transient flowmeter. A transient flow calibration facility consisting of a free-falling water column was also designed and built. Results of the calibrations are presented and show that the flowmeter can accurately measure transient flows up to the maximum observed acceleration of approximately 1 g.

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30

Karch, C., and Karl Roll. "Transient Simulation of Electromagnetic Forming of Aluminium Tubes." Advanced Materials Research 6-8 (May 2005): 639–48. http://dx.doi.org/10.4028/www.scientific.net/amr.6-8.639.

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The recent push to use more aluminium in automobiles has stimulated interest in understanding electromagnetic forming (EMF), which uses induced electromagnetic fields to generate high strain rates during the forming process. The high strain rates increase the formability of aluminum materials and might reduce elastic spring-back and wrinkling of the workpiece. Primary emphasis is placed on including of all relevant physical phenomena, which govern the process, as well as their numerical representation by means of simplified electrical equivalent circuits for the EMF machine and fully coupled field approach of the transient electromagnetic and mechanical phenomena. Moreover, the thermal effects due to Joule heating by eddy currents and plastic work are considered. The numerical model predicts the electromagnetic field, temperature, stress, and deformation properties that occur during the forming process. The numerical results of the tube deformation are compared with available experimental data.

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31

Liu, Wei. "Application of Embedded Technology in Transient Electromagnetic Receiver." Applied Mechanics and Materials 668-669 (October 2014): 791–94. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.791.

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The transient electromagnetic method (TEM), which is also called time domain electromagnetic method, is one of the common methods of geophysical disciplines of electrical prospecting. This paper, based on theory of the TEM, analysed the application of the embedded technology in TEM, and completed the design of the transient electromagnetic receiver system. The ARM processor is the core part of the system, combined with high precision A/D conversion chip, CPLD module, PC104 and other hardware parts.Through repeated field actual tests, the system works stably and reliably and data acquisition result is favourable.

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32

LIU, YING, and CHI XIE. "IMAGE RECOVERY OF TRANSIENT VOLTAGE BASED ON REAL-TIME MONITORING." Modern Physics Letters B 22, no. 05 (2008): 353–58. http://dx.doi.org/10.1142/s0217984908014821.

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In modern high-energy physics, a powerful electromagnetic field must be supplied for some elementary particles to be accelerated by passing through the region of high-energy physics fields. The electric current and high voltage producing the powerful electromagnetic field are very important to high-energy accelerators, but the insulation of electromagnetic coils in the accelerators suffers from electric damage under powerful electricity. Epecially, it may be stricken by transient overvoltage from the a.c. generator or electric network at any time. For the insulation problem of electromagnetic coils in the accelerator stricken by transient overvoltage, based on real-time monitoring and virtual image technique, the image recovery of transient voltage and the insulation safety of electromagnetic coils in the accelerator can be analyzed and predicted on-line.

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33

Albanese, Raffaele, Boris Bellesia, Roberto Palmaccio, et al. "Electromagnetic transient studies in the ITER tokamak." International Journal of Applied Electromagnetics and Mechanics 39, no. 1-4 (2012): 65–71. http://dx.doi.org/10.3233/jae-2012-1444.

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34

Qamar, Aamir, Inzamam Ul Haq, Majed Alhaisoni, and Nadia Nawaz Qadri. "Detecting Grounding Grid Orientation: Transient Electromagnetic Approach." Applied Sciences 9, no. 24 (2019): 5270. http://dx.doi.org/10.3390/app9245270.

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The configuration is essential to diagnose the status of the grounding grid, but the orientation of the unknown grounding grid is ultimately required to diagnose its configuration explicitly. This paper presents a transient electromagnetic method (TEM) to determine grounding grid orientation without excavation. Unlike the existing pathological solutions, TEM does not enhance the surrounding electromagnetic environment. A secondary magnetic field as a consequence of induced eddy currents is subjected to inversion calculation. The orientation of the grounding grid is diagnosed from the equivalent resistivity distribution against the circle perimeter. High equivalent resistivity at a point on the circle implies the grounding grid conductor and vice versa. Furthermore, various mesh configurations including the presence of a diagonal branch and unequal mesh spacing are taken into account. Simulations are performed using COMSOL Multiphysics and MATLAB to verify the usefulness of the proposed method.

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35

Marx, E. "Self-patch integrals in transient electromagnetic scattering." IEEE Transactions on Antennas and Propagation 33, no. 7 (1985): 763–67. http://dx.doi.org/10.1109/tap.1985.1143665.

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36

Morgan, M. A., and N. J. Walsh. "Ultra-wide-band transient electromagnetic scattering laboratory." IEEE Transactions on Antennas and Propagation 39, no. 8 (1991): 1230–34. http://dx.doi.org/10.1109/8.97361.

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37

Nowak, L., and K. Radziuk. "Transient analysis of PWM-excited electromagnetic actuators." IEE Proceedings - Science, Measurement and Technology 149, no. 5 (2002): 199–202. http://dx.doi.org/10.1049/ip-smt:20020543.

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38

Rogers, G. J., and D. Shirmohammadi. "Induction Machine Modelling for Electromagnetic Transient Program." IEEE Power Engineering Review PER-7, no. 12 (1987): 37–38. http://dx.doi.org/10.1109/mper.1987.5526837.

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39

Yang, Dong, Zhenxiang Liu, Ting Shu, Lijia Yang, Jianming Ouyang, and Shen Zhi. "Transient simulation of helical coil electromagnetic launchers." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, no. 1 (2018): 280–92. http://dx.doi.org/10.1108/compel-01-2017-0012.

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Purpose Helical coil electromagnetic launchers (HEMLs) using motion-induced commutation strategy solve the problem of synchronization control perfectly. HEMLs can meet the requirements of multiple applications such as the electromagnetic catapult, electromagnetic mortar and high-velocity coilgun. The trade-off between the velocity and efficiency is an important basis for these different applications. To optimize such objectives before actual design, the purpose of this paper is to focus on the efficient and flexible calculation model and algorithm. A novel structure of HEML is proposed after the transient simulation by this algorithm, which can improve the energy conversion efficiency and suppress the muzzle arc without affecting the velocity too much. Design/methodology/approach The equivalent circuit model of the launcher is established and the governing equations are derived. A combination of the four-stage Runge–Kutta method and the trapezoidal quadrature formula are used to solve the governing equations. Findings With smaller number of turns in the coils of HEML, the velocity is larger and the efficiency is lower. The non-uniform HEML is an effective option to improve the energy conversion efficiency and to suppress the muzzle arc with almost the same muzzle velocity as the conventional HEML. Originality/value The paper presents a common model and a flexible fast numerical method which can be used in multi-objective optimization of HEMLs such as the genetic algorithm. A new structure of the non-uniform HEML is proposed to improve the energy conversion efficiency and to suppress the muzzle arc of the launcher.

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40

Grcev, L. D., and F. E. Menter. "Transient electromagnetic fields near large earthing systems." IEEE Transactions on Magnetics 32, no. 3 (1996): 1525–28. http://dx.doi.org/10.1109/20.497540.

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41

Skotte, JH. "Exposure to high-frequency transient electromagnetic fields." Scandinavian Journal of Work, Environment & Health 22, no. 1 (1996): 39–44. http://dx.doi.org/10.5271/sjweh.107.

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42

Xie, Haiyan, Jianguo Wang, Dongyang Sun, and Ruyu Fan. "TRANSIENT ELECTROMAGNETIC TOPOLOGY AND ITS EXPERIMENTAL VALIDATION." Progress In Electromagnetics Research Letters 25 (2011): 185–95. http://dx.doi.org/10.2528/pierl11022702.

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43

Fu, Guo Hong, and Bin Xiong. "The Calculation of 2.5D Transient Electromagnetic Response." Applied Mechanics and Materials 36 (October 2010): 349–54. http://dx.doi.org/10.4028/www.scientific.net/amm.36.349.

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A 2.5D finite element forward algorithm for TEM with block linear conductivity was put forward in this paper. Firstly, based on the Maxwell equations, 2-order dual differential equation along strike was obtained by Laplace and Fourier transform. Then finite element linear equation system was obtained from coupling differential equation by using the Galerkin method, and yields the numerical solution of 2.5D transient electromagnetic field. The conductivity in finite element mesh is linear but uniform. In addition, the total field is decomposed into background field and secondary field: the former is solved by analytical method, and the latter is calculated by numerical method. Finally, 2.5D transient electromagnetic response curves of several typical geoelectric section models were computed.

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Hohmann, G. W., and G. A. Newman. "Transient electromagnetic responses of surficial, polarizable patches." GEOPHYSICS 55, no. 8 (1990): 1098–100. http://dx.doi.org/10.1190/1.1442921.

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Abnormal decay curves that are depressed or change sign often are observed in coincident‐loop and central‐loop transient electromagnetic (TEM) measurements, particularly in areas of conductive overburden. With the publication of papers by Smith and West (1989a, b) and Flis et al. (1989), the phenomenon, which is due to induced polarization (IP) in near‐surface, weakly polarizable material such as clay, is well understood.

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Maher, M. J. "Transient electromagnetic surveys in the Okiep district." GEOPHYSICS 57, no. 5 (1992): 736–44. http://dx.doi.org/10.1190/1.1443287.

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In the Okiep District early miners produced massive sulfide ore from some five deposits. Some of these deposits later contributed to the reserves of disseminated ore mined during modern times. It is unreasonable to assume that all of the massive sulfide bodies present within the area are intersected by the erosion surface and thus were discovered by the early miners. Consequently, blind massive sulfide ore bodies could be present and may have large quantities of disseminated ore associated with them. The transient electromagnetic method is ideally suited to exploring for massive sulfide bodies, and six test surveys were carried out at various sites in the district. Four of these surveys were unsuccessful whereas, at the remaining two sites, excellent anomalies were recorded. At Ezelsfontein East Extension an anomaly was recorded indicative of a massive sulfide body at shallow depth and of generally flat attitude. This anomaly has a time constant of 15 ms and the interpreted body was confirmed by a limited diamond drilling program. A deep, flat‐lying conductor was interpreted from the TEM results at Fonteintjie West Prospect. This anomaly, with a time constant of 0.6 ms, has limited size. Diamond drilling confirmed the presence of submassive to massive sulfide mineralization at this locale. Neither of these two drilled prospects had economic mineralization.

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El‐Kaliouby, Hesham M., and Essam A. Eldiwany. "Transient electromagnetic responses of 3D polarizable body." GEOPHYSICS 69, no. 2 (2004): 426–30. http://dx.doi.org/10.1190/1.1707062.

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The transient voltage response of a central loop electromagnetic system above a buried polarizable parallelepiped target (such as pyrites, sulfides, clays, etc.) is studied. The voltage response, which includes a positive part and a negative part (related to the polarization properties), is studied by varying the body characteristics, including the Cole‐Cole parameters, body dimensions, depth, and thickness. By varying the loop radius and by using profiling, the lateral body dimensions can be identified, particularly using the negative response for polarizable bodies. There is a clear difference in the dependencies of the positive and negative voltage responses on the body characteristics, which means that the negative voltage is not just redundant data, but we may use it, together with the positive response, to have better understanding for the body dimensions and polarization parameters effects.

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Hoole, P. Ratnamahilan P., and S. Ratnajeevan H. Hoole. "Computing transient electromagnetic fields radiated from lightning." Journal of Applied Physics 61, no. 8 (1987): 3473–75. http://dx.doi.org/10.1063/1.338760.

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Lee, S. K., and G. Buselli. "Underground and Down-hole Transient Electromagnetic Modelling." Exploration Geophysics 18, no. 1-2 (1987): 130–34. http://dx.doi.org/10.1071/eg987130.

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Rogers, G. J., and D. Shirmohammadi. "Induction Machine Modelling for Electromagnetic Transient Program." IEEE Transactions on Energy Conversion EC-2, no. 4 (1987): 622–28. http://dx.doi.org/10.1109/tec.1987.4765901.

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Diesinger, H., M. Panahandeh-Fard, Z. Wang, D. Baillargeat, and C. Soci. "Enhancing photocurrent transient spectroscopy by electromagnetic modeling." Review of Scientific Instruments 83, no. 5 (2012): 053103. http://dx.doi.org/10.1063/1.4710996.

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