To elucidate the characteristics and mechanism of electromagnetic radiation in granite under impact loading,based on the quasi-static compression tests,this paper conducts dynamic compression experiments on granite us...To elucidate the characteristics and mechanism of electromagnetic radiation in granite under impact loading,based on the quasi-static compression tests,this paper conducts dynamic compression experiments on granite using Hopkinson pressure bar and one-stage light-gas gun as loading methods.Combined with experimental and theoretical analyses,the relationship between mechanical and electromagnetic responses under impact loads of different intensities,and the time-domain signals of electromagnetic radiation generated by a single crack under different strain rates are studied.The intensity and frequency of electromagnetic radiation increase with the increasing compressive strain rate.According to the thermal activation theory,it reveals the microscopic mechanism of the transition from intergranular microcracks to transgranular microcracks in terms of strain sensitivity.It also serves as the physical basis for the increase in electromagnetic radiation intensity amplitude and frequency with increasing compressive strain rate.Transgranular microcracks are the primary cause of electromagnetic radiation generated by fractures.展开更多
Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the ai...Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the aid of a deep learning algorithm,a new method for the prediction of M-A-E data is proposed.In this method,an M-A-E data prediction model is built based on a variety of neural networks after analyzing numerous M-A-E data,and then the M-A-E data can be predicted.The predicted results are highly correlated with the real data collected in the field.Through field verification,the deep learning-based prediction method of M-A-E data provides quantitative prediction data for rockburst monitoring.展开更多
In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according ...In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation.展开更多
With the ever increasing application of electronic technology, our exposure to artificial electromagnetic energy is also rapidly increasing. Electromagnetic radiation (EMR) is the fourth largest source of pollution,...With the ever increasing application of electronic technology, our exposure to artificial electromagnetic energy is also rapidly increasing. Electromagnetic radiation (EMR) is the fourth largest source of pollution, after air, water, and noise.展开更多
Rock bursts are serious natural disasters encountered worldwide in coal mining and rock engineering.In order to forecast rock bursts more effectively,a new rock burst forecasting index E,consisting of intensity and th...Rock bursts are serious natural disasters encountered worldwide in coal mining and rock engineering.In order to forecast rock bursts more effectively,a new rock burst forecasting index E,consisting of intensity and the number of pulses,is proposed,on the basis of abnormal characteristic symptoms of electromagnetic radiation(EMR) generated before rock bursts,combined with statistical theory.The index is distributed as a χ2 distribution with 2 degrees of freedom,i.e.,E~χ 2(2).Via this index,a quantitative comprehensive forecasting criterion of EMR was initially established.E values were calculated when the occurrence probability of the occurrence of a rock burst was 50%,70% and 90%.Appropriate measures should be taken when using these values on the scene.Using EMR data collected in the Nanshan Mine of the Hegang mining area,we verified that the analytical result were consistent with actual situations.This index is of theoretical importance and as a reference for forecasting rock bursts in coal mines.展开更多
With the increasing knowledge of shortwave radiation,it is widely used in wireless communications,radar observations,industrial manufacturing,and medical treatments.Despite of the benefits from shortwave,these wide ap...With the increasing knowledge of shortwave radiation,it is widely used in wireless communications,radar observations,industrial manufacturing,and medical treatments.Despite of the benefits from shortwave,these wide applications expose humans to the risk of shortwave electromagnetic radiation,which is alleged to cause potential damage to biological systems.This review focused on the exposure to shortwave electromagnetic radiation,considering in vitro,in vivo and epidemiological results that have provided insight into the biological effects and mechanisms of shortwave.Additionally,some protective measures and suggestions are discussed here in the hope of obtaining more benefits from shortwave with fewer health risks.展开更多
More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine.We analyzed experimental observations and field data from the Muchengjian coal mine to study...More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine.We analyzed experimental observations and field data from the Muchengjian coal mine to study the relationship between electromagnetic radiation signal intensity and stress during the fracturing of coal, or rock, and samples under load.The results show that the signal intensity is positively correlated with stress.In addition, we investigated the change in the electromagnetic radiation intensity, the supporting resistance in a real coal mine environment, and the coal or rock stress in the mining area.The data analysis indicates that:1) electromagnetic radiation intensity can accurately reflect the distribution of stress in the mining area;and, 2) there is a correlation between electromagnetic radiation intensity and supporting resistance.The research has some practical guiding significance for rock burst forecasting and for the prevention of accidents in coal mines.展开更多
The influence of rock mechanical properties on the electromagnetic radiation(EMR)mechanism of rock fracturing is an important research topic in solid mechanics and earthquake prediction.In this study,an EMR model of r...The influence of rock mechanical properties on the electromagnetic radiation(EMR)mechanism of rock fracturing is an important research topic in solid mechanics and earthquake prediction.In this study,an EMR model of rock fracturing considering the fracture factor,elastic modulus,Poisson’s ratio,radiation distance and crack length is derived based on the Hertz oscillator array assumption.An experimental system,including an electromagnetic shielding module,an EMR signal induction and transmission module,a signal recording module and a loading module,is developed to understand the EMR characteristics of four different rocks.The validity of the EMR theoretical model is verified and the relationships between the rock cracking morphology and the EMR waveform,amplitude and frequency are revealed.It is found that rock mechanical properties have obvious influences on the EMR waveform,amplitude and frequency during rock fracturing.This study provides a better understanding on the EMR mechanism of rock fracturing and can help to improve the accuracy of rock disaster prediction based on EMR.展开更多
Electromagnetic radiation observations have been developed since the 1976 Tangshan earthquake.Up to now,130 observatories have been set up in China.The present observation frequency ranges are ultra-low frequency 0.01...Electromagnetic radiation observations have been developed since the 1976 Tangshan earthquake.Up to now,130 observatories have been set up in China.The present observation frequency ranges are ultra-low frequency 0.01-20 Hz and point frequency from 103 to 104 Hz.In the past 20 years,more than 40 earthquakes above M5.0 were recorded.By analyzing the earthquake examples,it is demonstrated that the distances between the anomalies recorded at observatories and the event were related with earthquake magnitude;the lasting time of anomalies are from several seconds to several ten days;during most of these events no electromagnetic radiation were observed simultaneously.In addition,the detail features of the electromagnetic radiation anomalies were discussed in this paper.展开更多
Based on electromagnetic radiation characteristics, the present research studied the damage evolution of rock under uniaxial compression. Besides, this research built the coal-rock damage evolution model considered re...Based on electromagnetic radiation characteristics, the present research studied the damage evolution of rock under uniaxial compression. Besides, this research built the coal-rock damage evolution model considered residual strength. The applicability and accuracy of the model were verified through experiments. The results show that coal-rock damage evolution consists of four periods. The first period is from the beginning of compression to nearly 20% of the stress peak value, during which the damage variable changes stably about 0.1, and accordingly a few of electromagnetic radiation signals emerge. The second period is from about 20% to 70% of the stress peak value. The damage has stable development, and the parameter of electromagnetic radiation characteristics turns larger continuously with the increase of stress. The third period is when the damage has accelerated development, the coal-rock was broken which result from sharp increasing of the damage variable, meanwhile a great quantity of electromagnetic radiation signals emerge. The fourth period is after the coal-rock fracture, during which the damage variable corresponding to the parameter of electromagnetic radiation characteristics has a stable development. This research has great academic and realistic significance for further studies the electromagnetic radiation characteristics of coal-rock under loading and damage and the forecasting of coal-rock dynamic disasters.展开更多
Based on the laboratory experiments this paper presented that the primary influence factors about the electromagnetic radiation during rock fracture are the rock mechanics characters and mineral components. The brittl...Based on the laboratory experiments this paper presented that the primary influence factors about the electromagnetic radiation during rock fracture are the rock mechanics characters and mineral components. The brittle samples and samples contained quartz, pyrite, chalopyrite produce electromagnetic radiation easily. There are three fracture radiation effects. The crystal fracture effect produces the high frequency electromagnetic signals, the piezoelectric effect produces low frequency signals and the natural semiconductor effect produces middle frequency signals possessed distinct wave shapes.展开更多
In this study,the characteristics of Electromagnetic(EM) radiation caused by Electrostatic Discharges(ESDs) from metal spheres charged to voltages less than 1 kV are examined experimentally.Our experimental system con...In this study,the characteristics of Electromagnetic(EM) radiation caused by Electrostatic Discharges(ESDs) from metal spheres charged to voltages less than 1 kV are examined experimentally.Our experimental system consists of a pair of spherical electrodes of different diameters,a 1-18 GHz-bandwidth horn antenna and a 20-GHz-bandwidth digitizing oscilloscope.Polarization,waveform duration and peaks of antenna-received voltages from the EM field radiation are measured in order to clarify the EM radiation mechanism.The ratio of the received voltages between the antenna arrangements of the field polarization parallel and perpendicular to the spark pass is 18 to 20 dB.The polarities of the antenna-received voltages are the same as those of the charge voltages across the gap.Moreover,the waveform duration and the first peaks increase with an increase in the diameters of the spherical electrodes.Consequently,we find that the polarization,waveform duration and first peaks of the EM field radiation can be explained by a dipole antenna structure,which makes the spark part of the spherical electrodes a feeding point on the straight line passing through the centres of the two spheres.展开更多
The cell-type continuous electromagnetic radiation system is a demonstration device capable of generating high-power millimeter electromagnetic waves of a specific wavelength and observing their effects on living orga...The cell-type continuous electromagnetic radiation system is a demonstration device capable of generating high-power millimeter electromagnetic waves of a specific wavelength and observing their effects on living organisms.It irradiates a biological sample placed in a 30×30×50 cm^(3)cell with electromagnetic waves in the 3.15-mm-wavelength region(with an output of≥1 W)and analyzes the temperature change of the sample.A vacuum electronic device-based coupled-cavity backward-wave oscillator converts the electron energy of the electron beam into radiofrequency(RF)energy and radiates it to the target through an antenna,increasing the temperature through the absorption of RF energy in the skin.The system causes pain and ultimately reduces combat power.A cell-type continuous electromagnetic radiation system consisting of four parts—an electromagnetic-wave generator,a highvoltage power supply,a test cell,and a system controller—generates an RF signal of≥1 W in a continuous waveform at a 95-GHz center frequency,as well as a chemical solution with a dielectric constant similar to that of the skin of a living organism.An increase of 5°C lasting approximately 10 s was confirmed through an experiment.展开更多
The electromagnetic radiation (EMR) signal collected by monitoring system during coal or rock dynamic disaster may be interferred easily by electromagnetic noises in mines. The noises have a direct influence on the ...The electromagnetic radiation (EMR) signal collected by monitoring system during coal or rock dynamic disaster may be interferred easily by electromagnetic noises in mines. The noises have a direct influence on the recognition and analysis of the EMR signal features during the disaster. With the aim of removing these noises, an ensemble empirical mode decomposition (EEMD) adaptive morphological filter was proposed. From the result of the simulation and the experiment, it is shown that the method can restrain the random noise and white Gaussian noise mixed with EMR signal effectively. The filter is highly useful for improving the robustness of the coal or rock dynamic disaster monitoring system.展开更多
The brain of humans and other organisms is affected in various ways through the electromagneticfield(EMF)radiations generated by mobile phones and cell phone towers.Morphological variations in the brain are caused by t...The brain of humans and other organisms is affected in various ways through the electromagneticfield(EMF)radiations generated by mobile phones and cell phone towers.Morphological variations in the brain are caused by the neurological changes due to the revelation of EMF.Cellular level analysis is used to measure and detect the effect of mobile radiations,but its utilization seems very expensive,and it is a tedious process,where its analysis requires the preparation of cell suspension.In this regard,this research article proposes optimal broadcast-ing learning to detect changes in brain morphology due to the revelation of EMF.Here,Drosophila melanogaster acts as a specimen under the revelation of EMF.Automatic segmentation is performed for the brain to attain the microscopic images from the prejudicial geometrical characteristics that are removed to detect the effect of revelation of EMF.The geometrical characteristics of the brain image of that is microscopic segmented are analyzed.Analysis results reveal the occur-rence of several prejudicial characteristics that can be processed by machine learn-ing techniques.The important prejudicial characteristics are given to four varieties of classifiers such as naïve Bayes,artificial neural network,support vector machine,and unsystematic forest for the classification of open or nonopen micro-scopic image of D.melanogaster brain.The results are attained through various experimental evaluations,and the said classifiers perform well by achieving 96.44%using the prejudicial characteristics chosen by the feature selection meth-od.The proposed system is an optimal approach that automatically identifies the effect of revelation of EMF with minimal time complexity,where the machine learning techniques produce an effective framework for image processing.展开更多
The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attr...The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attraction) from its presumed association with cosmic rays. Cosmic ray delivered KELEA is viewed as normally participating in the formation of cloud condensation nuclei (CCN). It may do so by transforming electrostatically inert particles into electrostatic aerosols capable of acting as CCN. The resulting clouds act as a reflective barrier to some of the infrared radiation from the sun and, thereby, reduce the earth’s heat. This article proposes that increasing levels of electromagnetic radiation in the atmosphere is reducing the capacity of cosmic rays to deliver adequate KELEA to maintain climate stability through optimal cloud formation. Specifically, the fluctuating electrical fields accompanying electromagnetic radiation may do so by competitively withdrawing some of the KELEA from the incoming cosmic rays. Previously described studies by Dr. Wilhelm Reich attributed to an energy force termed orgone, are consistent with weather activity being inducible using a device that likely delivers KELEA to the atmosphere. In addition to the foregoing consideration, there are many agricultural and industrial applications of KELEA activated fluids that can reduce carbon emissions. It is important that the scope of climate science be broadened to include a detailed understanding of KELEA and of its many potential practical applications in addressing global warming.展开更多
This study examined the impact of 935MHz phone-simulating electromagnetic radiation on embryo implantation of pregnant mice.Each 7-week-old Kunming (KM) female white mouse was set up with a KM male mouse in a single c...This study examined the impact of 935MHz phone-simulating electromagnetic radiation on embryo implantation of pregnant mice.Each 7-week-old Kunming (KM) female white mouse was set up with a KM male mouse in a single cage for mating overnight after induction of ovulation.In the first three days of pregnancy,the pregnant mice was exposed to electromagnetic radiation at low-intensity (150 μW/cm2,ranging from 130 to 200 μW/cm2,for 2-or 4-h exposure every day),mid-intensity (570 μW/cm2,ranging from 400 to 700 μW/cm2,for 2-or 4-h exposure every day) or high-intensity (1400 μW/cm2,ranging from 1200 to 1500 μW/cm2,for 2-or 4-h exposure every day),respectively.On the day 4 after gestation (known as the window of murine embryo implantation),the endometrium was collected and the suspension of endometrial glandular cells was made.Laser scanning microscopy was employed to detect the mitochondrial membrane potential and intracellular calcium ion concentration.In high-intensity,2-and 4-h groups,mitochondrial membrane potential of endometrial glandular cells was significantly lower than that in the normal control group (P<0.05).The calcium ion concentration was increased in low-intensity 2-h group but decreased in high-intensity 4-h group as compared with the normal control group (P<0.05).However,no significant difference was found in mitochondrial membrane potential of endometrial glandular cells between low-or mid-intensity groups and the normal control group,indicating stronger intensity of the electromagnetic radiation and longer length of the radiation are required to inflict a remarkable functional and structural damage to mitochondrial membrane.Our data demonstrated that electromagnetic radiation with a 935-MHz phone for 4 h conspicuously decreased mitochondrial membrane potential and lowered the calcium ion concentration of endometrial glandular cells.It is suggested that high-intensity electromagnetic radiation is very likely to induce the death of embryonic cells and decrease the chance of their implantation,thereby posing a high risk to pregnancy.展开更多
The plasma wake of reentry vehicles has the advantages of extensive space range and long traceability,which provides new possibilities for the detection and monitoring of reentry vehicles.Based on the Zakharov model,t...The plasma wake of reentry vehicles has the advantages of extensive space range and long traceability,which provides new possibilities for the detection and monitoring of reentry vehicles.Based on the Zakharov model,this work investigates the excitation and power spectrum characteristics of electromagnetic radiation for the plasma wake of a typical reentry vehicle.With the aid of parametric decay instability,the excitation condition of electromagnetic radiation for a typical plasma wake is evaluated first.The power spectrum characteristics of electromagnetic radiation,including the effects of both the flight parameters and incident wave parameters are analyzed in detail.The results show that when the phenomenon of excited electromagnetic radiation occurs,plasma wakes closer to the bottom of the vehicle and with faster speeds require higher incident frequencies and thresholds of the electric field.As the frequency of the incident wave increases,peaks appear in the power spectra of plasma wakes,and their magnitudes increase gradually.The frequency shifts of the secondary peaks are equal,whereas,the peaks of the downshifted spectral lines are generally larger than those of the upshifted spectral lines.The work in this paper provides a new idea and method for the tracking of reentry vehicles,which has potential application value in the field of reentry vehicle detection.展开更多
In order to investigate the physical mechanism of non-synchronism of seismo-electromagnetic radiation precursors, we have made shear fracture and frictional sliding tests of rock samples by loading them in biaxial com...In order to investigate the physical mechanism of non-synchronism of seismo-electromagnetic radiation precursors, we have made shear fracture and frictional sliding tests of rock samples by loading them in biaxial compression to model the activity of tectonic fault zones in seismogenic region. By installing antennae of different frequency responses and acoustic transducers around the fracture surface, the signals of electromagnetic radiation and acoustic emission in different directions and of different frequencies produced by rock samples during their shear fracturing and frictional sliding have been recorded by an automatic, high-speed and continuous observation system. Some implications given by the experimental results are as follows. (1) During the process of shear fracturing and frictional sliding of rock samples under biaxial compression, large amounts of electromagnetic signals are produced; their frequencies range from several hundred Hz to several thousand Hz. (2) Signals received by antennae in different directions and of different frequencies are non-synchronous. They differ in amplitude from one another, with the signal received by antennae nearest to the fracture surface being the maximum. (3) Electric signals and magnetic signals do not appear synchronously; among them, electric signals appear more frequently and are of larger amplitude. The authors hold that electric signals (E) and magnetic signals (M) are of different genetic mechanisms: electric signals from inside the rock sample are produced by the piezoelectric effect of rock-forming crystals and net electric charge produced by the newly created surfaces due to rock fracture, whereas magnetic signals are produced by the high-speed motion of charged rock fragments and the ionization of ambient air excited by electrons emitted by rock in fracturing. Analysis shows that in some moderately strong earthquakes the electric and magnetic signals also showed the phenomenon of non-synchronism: the electric signal was earlier than the magnetic signal. If the same station observes simultaneously the electric field (underground) and magnetic field (air), the efficiency of earthquake prediction by seismo-electromagnetic radiation precursors would be raised effectively.展开更多
基金supported by the National Natural Science Foundation of China(No.62227901)。
文摘To elucidate the characteristics and mechanism of electromagnetic radiation in granite under impact loading,based on the quasi-static compression tests,this paper conducts dynamic compression experiments on granite using Hopkinson pressure bar and one-stage light-gas gun as loading methods.Combined with experimental and theoretical analyses,the relationship between mechanical and electromagnetic responses under impact loads of different intensities,and the time-domain signals of electromagnetic radiation generated by a single crack under different strain rates are studied.The intensity and frequency of electromagnetic radiation increase with the increasing compressive strain rate.According to the thermal activation theory,it reveals the microscopic mechanism of the transition from intergranular microcracks to transgranular microcracks in terms of strain sensitivity.It also serves as the physical basis for the increase in electromagnetic radiation intensity amplitude and frequency with increasing compressive strain rate.Transgranular microcracks are the primary cause of electromagnetic radiation generated by fractures.
基金supported by the National Natural Science Foundation of China(Grant No.51934007)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20220691).
文摘Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the aid of a deep learning algorithm,a new method for the prediction of M-A-E data is proposed.In this method,an M-A-E data prediction model is built based on a variety of neural networks after analyzing numerous M-A-E data,and then the M-A-E data can be predicted.The predicted results are highly correlated with the real data collected in the field.Through field verification,the deep learning-based prediction method of M-A-E data provides quantitative prediction data for rockburst monitoring.
文摘In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation.
基金supported by the National Natural Science Foundation of China[No.31570847]
文摘With the ever increasing application of electronic technology, our exposure to artificial electromagnetic energy is also rapidly increasing. Electromagnetic radiation (EMR) is the fourth largest source of pollution, after air, water, and noise.
基金supported by the National High Technology Research and Development Program of China (No.2006AA06Z119)the Ministry of Education Support Program for New Century Excellent Talent (No.NCET-06-0477)
文摘Rock bursts are serious natural disasters encountered worldwide in coal mining and rock engineering.In order to forecast rock bursts more effectively,a new rock burst forecasting index E,consisting of intensity and the number of pulses,is proposed,on the basis of abnormal characteristic symptoms of electromagnetic radiation(EMR) generated before rock bursts,combined with statistical theory.The index is distributed as a χ2 distribution with 2 degrees of freedom,i.e.,E~χ 2(2).Via this index,a quantitative comprehensive forecasting criterion of EMR was initially established.E values were calculated when the occurrence probability of the occurrence of a rock burst was 50%,70% and 90%.Appropriate measures should be taken when using these values on the scene.Using EMR data collected in the Nanshan Mine of the Hegang mining area,we verified that the analytical result were consistent with actual situations.This index is of theoretical importance and as a reference for forecasting rock bursts in coal mines.
文摘With the increasing knowledge of shortwave radiation,it is widely used in wireless communications,radar observations,industrial manufacturing,and medical treatments.Despite of the benefits from shortwave,these wide applications expose humans to the risk of shortwave electromagnetic radiation,which is alleged to cause potential damage to biological systems.This review focused on the exposure to shortwave electromagnetic radiation,considering in vitro,in vivo and epidemiological results that have provided insight into the biological effects and mechanisms of shortwave.Additionally,some protective measures and suggestions are discussed here in the hope of obtaining more benefits from shortwave with fewer health risks.
基金Projects 50427401 supported by the National Natural Science Foundation of China2006AA06Z119 by the Hi-tech Research and Development Program of China+2 种基金NCET-06-0477 by the New Century Excellent Talent Plan of Ministry of Education2007A002 by the Science & Research Foundation for Youth of China University of Mining and Technologythe Na-tional Basic Research Program of China (2005cb221505)
文摘More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine.We analyzed experimental observations and field data from the Muchengjian coal mine to study the relationship between electromagnetic radiation signal intensity and stress during the fracturing of coal, or rock, and samples under load.The results show that the signal intensity is positively correlated with stress.In addition, we investigated the change in the electromagnetic radiation intensity, the supporting resistance in a real coal mine environment, and the coal or rock stress in the mining area.The data analysis indicates that:1) electromagnetic radiation intensity can accurately reflect the distribution of stress in the mining area;and, 2) there is a correlation between electromagnetic radiation intensity and supporting resistance.The research has some practical guiding significance for rock burst forecasting and for the prevention of accidents in coal mines.
基金supported by the National Natural Science Foundation of China(Grant Nos.51979146 and 11272178)。
文摘The influence of rock mechanical properties on the electromagnetic radiation(EMR)mechanism of rock fracturing is an important research topic in solid mechanics and earthquake prediction.In this study,an EMR model of rock fracturing considering the fracture factor,elastic modulus,Poisson’s ratio,radiation distance and crack length is derived based on the Hertz oscillator array assumption.An experimental system,including an electromagnetic shielding module,an EMR signal induction and transmission module,a signal recording module and a loading module,is developed to understand the EMR characteristics of four different rocks.The validity of the EMR theoretical model is verified and the relationships between the rock cracking morphology and the EMR waveform,amplitude and frequency are revealed.It is found that rock mechanical properties have obvious influences on the EMR waveform,amplitude and frequency during rock fracturing.This study provides a better understanding on the EMR mechanism of rock fracturing and can help to improve the accuracy of rock disaster prediction based on EMR.
文摘Electromagnetic radiation observations have been developed since the 1976 Tangshan earthquake.Up to now,130 observatories have been set up in China.The present observation frequency ranges are ultra-low frequency 0.01-20 Hz and point frequency from 103 to 104 Hz.In the past 20 years,more than 40 earthquakes above M5.0 were recorded.By analyzing the earthquake examples,it is demonstrated that the distances between the anomalies recorded at observatories and the event were related with earthquake magnitude;the lasting time of anomalies are from several seconds to several ten days;during most of these events no electromagnetic radiation were observed simultaneously.In addition,the detail features of the electromagnetic radiation anomalies were discussed in this paper.
基金provided by the National Key Technology R&D Program of China (No. 2012BAK09B01)the National Natural Science Foundation of China (Nos. 50904067 and 51104156)+1 种基金the Program for the New Century Excellent Talents in University of China (No. NCET-10-0768)the Jiangsu Planned Projects for Postdoctoral Research Funds of China (No. 1102085C)
文摘Based on electromagnetic radiation characteristics, the present research studied the damage evolution of rock under uniaxial compression. Besides, this research built the coal-rock damage evolution model considered residual strength. The applicability and accuracy of the model were verified through experiments. The results show that coal-rock damage evolution consists of four periods. The first period is from the beginning of compression to nearly 20% of the stress peak value, during which the damage variable changes stably about 0.1, and accordingly a few of electromagnetic radiation signals emerge. The second period is from about 20% to 70% of the stress peak value. The damage has stable development, and the parameter of electromagnetic radiation characteristics turns larger continuously with the increase of stress. The third period is when the damage has accelerated development, the coal-rock was broken which result from sharp increasing of the damage variable, meanwhile a great quantity of electromagnetic radiation signals emerge. The fourth period is after the coal-rock fracture, during which the damage variable corresponding to the parameter of electromagnetic radiation characteristics has a stable development. This research has great academic and realistic significance for further studies the electromagnetic radiation characteristics of coal-rock under loading and damage and the forecasting of coal-rock dynamic disasters.
文摘Based on the laboratory experiments this paper presented that the primary influence factors about the electromagnetic radiation during rock fracture are the rock mechanics characters and mineral components. The brittle samples and samples contained quartz, pyrite, chalopyrite produce electromagnetic radiation easily. There are three fracture radiation effects. The crystal fracture effect produces the high frequency electromagnetic signals, the piezoelectric effect produces low frequency signals and the natural semiconductor effect produces middle frequency signals possessed distinct wave shapes.
文摘In this study,the characteristics of Electromagnetic(EM) radiation caused by Electrostatic Discharges(ESDs) from metal spheres charged to voltages less than 1 kV are examined experimentally.Our experimental system consists of a pair of spherical electrodes of different diameters,a 1-18 GHz-bandwidth horn antenna and a 20-GHz-bandwidth digitizing oscilloscope.Polarization,waveform duration and peaks of antenna-received voltages from the EM field radiation are measured in order to clarify the EM radiation mechanism.The ratio of the received voltages between the antenna arrangements of the field polarization parallel and perpendicular to the spark pass is 18 to 20 dB.The polarities of the antenna-received voltages are the same as those of the charge voltages across the gap.Moreover,the waveform duration and the first peaks increase with an increase in the diameters of the spherical electrodes.Consequently,we find that the polarization,waveform duration and first peaks of the EM field radiation can be explained by a dipole antenna structure,which makes the spark part of the spherical electrodes a feeding point on the straight line passing through the centres of the two spheres.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.NRF-2021M2E8A1038938,No.NRF-2021R1F1A1048374,and No.NRF-2016R1A3B1908336)supported by a grant of the Korea Institute of Radiological and Medical Sciences(KIRAMS),funded by the Ministry of Science and ICT(MSIT),Republic of Korea(No.50051—2021,No.50623—2021)。
文摘The cell-type continuous electromagnetic radiation system is a demonstration device capable of generating high-power millimeter electromagnetic waves of a specific wavelength and observing their effects on living organisms.It irradiates a biological sample placed in a 30×30×50 cm^(3)cell with electromagnetic waves in the 3.15-mm-wavelength region(with an output of≥1 W)and analyzes the temperature change of the sample.A vacuum electronic device-based coupled-cavity backward-wave oscillator converts the electron energy of the electron beam into radiofrequency(RF)energy and radiates it to the target through an antenna,increasing the temperature through the absorption of RF energy in the skin.The system causes pain and ultimately reduces combat power.A cell-type continuous electromagnetic radiation system consisting of four parts—an electromagnetic-wave generator,a highvoltage power supply,a test cell,and a system controller—generates an RF signal of≥1 W in a continuous waveform at a 95-GHz center frequency,as well as a chemical solution with a dielectric constant similar to that of the skin of a living organism.An increase of 5°C lasting approximately 10 s was confirmed through an experiment.
文摘The electromagnetic radiation (EMR) signal collected by monitoring system during coal or rock dynamic disaster may be interferred easily by electromagnetic noises in mines. The noises have a direct influence on the recognition and analysis of the EMR signal features during the disaster. With the aim of removing these noises, an ensemble empirical mode decomposition (EEMD) adaptive morphological filter was proposed. From the result of the simulation and the experiment, it is shown that the method can restrain the random noise and white Gaussian noise mixed with EMR signal effectively. The filter is highly useful for improving the robustness of the coal or rock dynamic disaster monitoring system.
文摘The brain of humans and other organisms is affected in various ways through the electromagneticfield(EMF)radiations generated by mobile phones and cell phone towers.Morphological variations in the brain are caused by the neurological changes due to the revelation of EMF.Cellular level analysis is used to measure and detect the effect of mobile radiations,but its utilization seems very expensive,and it is a tedious process,where its analysis requires the preparation of cell suspension.In this regard,this research article proposes optimal broadcast-ing learning to detect changes in brain morphology due to the revelation of EMF.Here,Drosophila melanogaster acts as a specimen under the revelation of EMF.Automatic segmentation is performed for the brain to attain the microscopic images from the prejudicial geometrical characteristics that are removed to detect the effect of revelation of EMF.The geometrical characteristics of the brain image of that is microscopic segmented are analyzed.Analysis results reveal the occur-rence of several prejudicial characteristics that can be processed by machine learn-ing techniques.The important prejudicial characteristics are given to four varieties of classifiers such as naïve Bayes,artificial neural network,support vector machine,and unsystematic forest for the classification of open or nonopen micro-scopic image of D.melanogaster brain.The results are attained through various experimental evaluations,and the said classifiers perform well by achieving 96.44%using the prejudicial characteristics chosen by the feature selection meth-od.The proposed system is an optimal approach that automatically identifies the effect of revelation of EMF with minimal time complexity,where the machine learning techniques produce an effective framework for image processing.
文摘The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attraction) from its presumed association with cosmic rays. Cosmic ray delivered KELEA is viewed as normally participating in the formation of cloud condensation nuclei (CCN). It may do so by transforming electrostatically inert particles into electrostatic aerosols capable of acting as CCN. The resulting clouds act as a reflective barrier to some of the infrared radiation from the sun and, thereby, reduce the earth’s heat. This article proposes that increasing levels of electromagnetic radiation in the atmosphere is reducing the capacity of cosmic rays to deliver adequate KELEA to maintain climate stability through optimal cloud formation. Specifically, the fluctuating electrical fields accompanying electromagnetic radiation may do so by competitively withdrawing some of the KELEA from the incoming cosmic rays. Previously described studies by Dr. Wilhelm Reich attributed to an energy force termed orgone, are consistent with weather activity being inducible using a device that likely delivers KELEA to the atmosphere. In addition to the foregoing consideration, there are many agricultural and industrial applications of KELEA activated fluids that can reduce carbon emissions. It is important that the scope of climate science be broadened to include a detailed understanding of KELEA and of its many potential practical applications in addressing global warming.
基金supported by the National Natural Science Foundation of China (No.30670509)
文摘This study examined the impact of 935MHz phone-simulating electromagnetic radiation on embryo implantation of pregnant mice.Each 7-week-old Kunming (KM) female white mouse was set up with a KM male mouse in a single cage for mating overnight after induction of ovulation.In the first three days of pregnancy,the pregnant mice was exposed to electromagnetic radiation at low-intensity (150 μW/cm2,ranging from 130 to 200 μW/cm2,for 2-or 4-h exposure every day),mid-intensity (570 μW/cm2,ranging from 400 to 700 μW/cm2,for 2-or 4-h exposure every day) or high-intensity (1400 μW/cm2,ranging from 1200 to 1500 μW/cm2,for 2-or 4-h exposure every day),respectively.On the day 4 after gestation (known as the window of murine embryo implantation),the endometrium was collected and the suspension of endometrial glandular cells was made.Laser scanning microscopy was employed to detect the mitochondrial membrane potential and intracellular calcium ion concentration.In high-intensity,2-and 4-h groups,mitochondrial membrane potential of endometrial glandular cells was significantly lower than that in the normal control group (P<0.05).The calcium ion concentration was increased in low-intensity 2-h group but decreased in high-intensity 4-h group as compared with the normal control group (P<0.05).However,no significant difference was found in mitochondrial membrane potential of endometrial glandular cells between low-or mid-intensity groups and the normal control group,indicating stronger intensity of the electromagnetic radiation and longer length of the radiation are required to inflict a remarkable functional and structural damage to mitochondrial membrane.Our data demonstrated that electromagnetic radiation with a 935-MHz phone for 4 h conspicuously decreased mitochondrial membrane potential and lowered the calcium ion concentration of endometrial glandular cells.It is suggested that high-intensity electromagnetic radiation is very likely to induce the death of embryonic cells and decrease the chance of their implantation,thereby posing a high risk to pregnancy.
基金supported by National Natural Science Foundation of China(Nos.62171355,61875156)the 111Project(No.B17035)+1 种基金the Natural Science Basic Research Program of Shaanxi Province(No.2021JM-135)the Stable Support Project of Basic Scientific Research Institutes(Nos.A131901W14,A132001W12)。
文摘The plasma wake of reentry vehicles has the advantages of extensive space range and long traceability,which provides new possibilities for the detection and monitoring of reentry vehicles.Based on the Zakharov model,this work investigates the excitation and power spectrum characteristics of electromagnetic radiation for the plasma wake of a typical reentry vehicle.With the aid of parametric decay instability,the excitation condition of electromagnetic radiation for a typical plasma wake is evaluated first.The power spectrum characteristics of electromagnetic radiation,including the effects of both the flight parameters and incident wave parameters are analyzed in detail.The results show that when the phenomenon of excited electromagnetic radiation occurs,plasma wakes closer to the bottom of the vehicle and with faster speeds require higher incident frequencies and thresholds of the electric field.As the frequency of the incident wave increases,peaks appear in the power spectra of plasma wakes,and their magnitudes increase gradually.The frequency shifts of the secondary peaks are equal,whereas,the peaks of the downshifted spectral lines are generally larger than those of the upshifted spectral lines.The work in this paper provides a new idea and method for the tracking of reentry vehicles,which has potential application value in the field of reentry vehicle detection.
文摘In order to investigate the physical mechanism of non-synchronism of seismo-electromagnetic radiation precursors, we have made shear fracture and frictional sliding tests of rock samples by loading them in biaxial compression to model the activity of tectonic fault zones in seismogenic region. By installing antennae of different frequency responses and acoustic transducers around the fracture surface, the signals of electromagnetic radiation and acoustic emission in different directions and of different frequencies produced by rock samples during their shear fracturing and frictional sliding have been recorded by an automatic, high-speed and continuous observation system. Some implications given by the experimental results are as follows. (1) During the process of shear fracturing and frictional sliding of rock samples under biaxial compression, large amounts of electromagnetic signals are produced; their frequencies range from several hundred Hz to several thousand Hz. (2) Signals received by antennae in different directions and of different frequencies are non-synchronous. They differ in amplitude from one another, with the signal received by antennae nearest to the fracture surface being the maximum. (3) Electric signals and magnetic signals do not appear synchronously; among them, electric signals appear more frequently and are of larger amplitude. The authors hold that electric signals (E) and magnetic signals (M) are of different genetic mechanisms: electric signals from inside the rock sample are produced by the piezoelectric effect of rock-forming crystals and net electric charge produced by the newly created surfaces due to rock fracture, whereas magnetic signals are produced by the high-speed motion of charged rock fragments and the ionization of ambient air excited by electrons emitted by rock in fracturing. Analysis shows that in some moderately strong earthquakes the electric and magnetic signals also showed the phenomenon of non-synchronism: the electric signal was earlier than the magnetic signal. If the same station observes simultaneously the electric field (underground) and magnetic field (air), the efficiency of earthquake prediction by seismo-electromagnetic radiation precursors would be raised effectively.