Dissertations / Theses on the topic 'Electromagnetic fields (EMF)'
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Lech, James Chrystopher. "Constructing an EMF radiation Hygeia framework and model to demonstrate a public interest override." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/58695.
Full textLoughran, Sarah Patricia, and n/a. "The efffects of eletromagnetic fields emitted by mobile phones on human sleep and melatonin production." Swinburne University of Technology, 2007. http://adt.lib.swin.edu.au./public/adt-VSWT20070731.100218.
Full textFunk, Richard H. W., and Thomas K. Monsees. "Effects of Electromagnetic Fields on Cells: Physiological and Therapeutical Approaches and Molecular Mechanisms of Interaction." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-136228.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
Funk, Richard H. W., and Thomas K. Monsees. "Effects of Electromagnetic Fields on Cells: Physiological and Therapeutical Approaches and Molecular Mechanisms of Interaction." Karger, 2006. https://tud.qucosa.de/id/qucosa%3A27702.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
McIntyre, Andrew III. "Behavioral responses of sub-adult Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus) to electromagnetic and magnetic fields under laboratory conditions." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4866.
Full textVila, Rodríguez Javier 1974. "INTEROCC : Occupational exposure assessment for electromagnetic fields and risk of brain tumours. Development of a new source-based approach." Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/543850.
Full textIntroduction: To improve exposure assessment methods for electromagnetic fields, we developed a methodology based on sources of exposure rather than job titles. Methods: Measurements collected from the literature were assessed and summarized into a source-exposure matrix (SEM). The SEM and personal determinants of exposure were combined to obtain individual indices cumulative exposure, which were used to assess risk of brain tumours, glioma an meningioma Results: Over 3,000 records were obtained and judged useful, creating a SEM with exposure estimates for 312 EMF sources. Overall the analysis yielded no association between glioma or meningioma risk and cumulative exposure to RF or IF EMF. However, some positive associations were identified for RF and IF EMF in the highest exposed groups in the 1- to 4-year exposure window for glioma, and in all windows for meningioma and RF only. These results might reflect a possible role of high frequency EMF in the later stages of carcinogenesis (promotion and progression).
Blood, Alan Physics Faculty of Science UNSW. "Biological effects of GSM mobile phone microwave radiation: an investigation of gene expression." Awarded by:University of New South Wales. School of Physics, 2005. http://handle.unsw.edu.au/1959.4/22071.
Full textLacy-Hulbert, Adam. "EMFs and gene activation." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364278.
Full textKimn, Edward Sun. "A parametric finite element analysis study of a lab-scale electromagnetic launcher." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39498.
Full textCulligan, Allan James. "The electromagnetic fields from a two-wire transmission line." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267710.
Full textŠvec, Marek. "Měření vlastností stíněných komor EMC." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217787.
Full textGyawali, Shashi Raj. "Design and construction of helmholtz coil for biomagnetic studies on soybean." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5686.
Full textThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 12, 2009) Includes bibliographical references.
Lévy, Pierre-Etienne. "Modélisation du rayonnement électromagnétique quasi-statique des composants magnétiques de puissance - Application à la compatibilité EM -." Thesis, Cachan, Ecole normale supérieure, 2015. http://www.theses.fr/2015DENS0019/document.
Full textThe number of electronic devices in embedded systems is constantly increasing and their contribution to volume and weight is a major concern. In order to solve these issues, a large research effort is devoted to volume reduction and power converters' integration. This lead to constant technological evolution including the appearance of high frequency power electronic converters allowing the reduction of the volume of passive components.However, due to the increase of operating frequencies and the minimization of inter-components distances, the electromagnetic radiations generated by these systems become more important. In order to decrease this interference, EMI filters are often necessary. Their performances are often related to the value of parasitic elements in the filter which must therefore be controlled. Nonetheless most of the existing models focus on conducted electromagnetic interference (EMI) and the impact of radiated phenomena is often ignored or greatly simplified. This work will therefore focus on developing highly accurate radiation models for magnetic components commonly used in EMI filters using both numeric and analytic tools.First, the magnetic fields radiated by differential mode (MD) toroidal coils, which belong to the basic magnetic components, will be thoroughly studied. This study highlighted the critical parameters determining the near-field topology. The main result is the discovery of the impact of the winding's layout around the magnetic core on the radiated magnetic field. New models have been developed in order to predict the radiated near field.Then, an accurate analytic model of the the magnetic radiation of common-mode (CM) chokes has been developed. It allows the prediction of the magnetic near-field. The application of the model lead to the correlation between radiated phenomena and conducted effects existing in these components. The importance of the winding on CM to DM mode coupling has therefore been highlighted.Finally, the electromagnetic (EM) susceptibility of these components has been studied. This work describes the influence of an external magnetic field on the components and validates the radiation models developed using the principle of EM reciprocity. It has been shown that the easy directions are the same for both the radiated and the coupled phenomena
Rodriguez, Maria A. (Maria Angeles) 1958. "Physiological responses to 60 Hz electric and magnetic fields in dairy cows under short photoperiod conditions." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84426.
Full textBurchard, Javier F. "Effects of 60 Hz electric and magnetic fields on productivity, reproductive hormones, plasma minerals and minerals and neurotransmitter metabolites in cerebrospinal fluid in dairy cattle." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41992.
Full textMilk production and composition, feed consumption, blood hormonal profiles and cerebrospinal fluid (CSF) components were assessed during the different periods of exposure. Most of the variables assessed were not affected by EMF. However, there was a positive association between EMF and feed consumption, milk fat content, blood plasma progesterone during pregnancy and estrous cycle length. Also, there were changes in the mineral and neurotransmitter metabolite concentrations in the CSF that showed a relationship to the EMF.
In conclusion, it could be stated that EMF caused a biological response in dairy cattle. It is speculated that these changes do not represent a health hazard for exposed cattle, although they warrant further research.
Barzegaran, Mohammadreza. "Physics-Based Modeling of Power System Components for the Evaluation of Low-Frequency Radiated Electromagnetic Fields." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1239.
Full textHung, Ching-Sui. "Effects of pulse-modulated microwave radiation from mobile phones on the sleep/waking EEG and psychomotor vigilance." Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/15747.
Full textJomaa, Kassem. "Caractérisation du champ proche électromagnétique et exposition professionnelle aux ondes RF en milieu industriel." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT111/document.
Full textThe analysis of radiated emissions from a source throughout the space, is very essential for both dosimetric and electromagnetic interference analysis. The concerns about the latter are growing because of the need to have prediction of the system reliability of the electronic circuits. Moreover the everyday use of devices and systems emitting radio frequency electromagnetic fields is continuously increasing. Some of these devices are operating in the vicinity of human body, and operators are in the near-field region of the radiating source, and they are exposed to electromagnetic fields. For this reason, dosimetric analysis, that shows the necessity of having three dimensional (3D) field mapping in the vicinity of the radiating source, should be performed. For this kind of applications, several scans of the near fields should be done within different planes in order to build the 3D field mapping. Being a challenging process in electromagnetic compatibility studies, near field characterization is being treated by several algorithms that propose different approaches to achieve the required scanning on the radiating source.In this work, we introduce a 3D scanning system with a low cost three axis magnetic field probes. Having such probes allow the simultaneous measure of the three components of the magnetic field based on a single planner scan above the device under test. The designed probes consist of three orthogonal loops combined together; the first probe contains three conventional loops joined in a plastic cube with a total dimension of 10×12×13 mm3, whereas the second probe is a PCB probe printed on an FR4 substrate of 3.2 mm with a reduced dimension of 9×9×3.2 mm3. The designed probes were calibrated with a TEM cell and the corresponding antenna factors were extracted. The presented scanning system uses an oscilloscope as a measuring instrument that gives the possibility of both time and frequency domain measurements. The second part of this thesis presents a reconstruction algorithm based on plane wave spectrum method. In order to reduce the number of scans and hence the time requirements, the presented algorithm requires just a 2D near field scan of the field components, to reconstruct the 3D magnetic field distribution above the radiating device.The third part of the thesis is devoted for the dosimetric analysis of the radiated electromagnetic fields near RFID systems and RF-welding machines. The near-field exposure assessment of the radiated fields from RFID reader antennas operating at 13.56 MHz and used in Libraries was performed. The measurements of the magnetic field near the antenna were established using the designed probes. The results are then analyzed and compared to the regulations in European Directives and ICNIRP Guidelines. Moreover, the exposure to RF electromagnetic fields of workers near RF-welding machines in industrial environment is studied. These machines, operating at 27 MHz, emit strong radiation and the exposure takes place in the near-field region. The spatial distribution of the electromagnetic fields in this region is studied in both numerical simulations and measurements
Mohammad, Mostak. "Optimization of Inductive Wireless Charging Systems for Electric Vehicles: Minimizing Magnetic Losses and Limiting Electromagnetic Field Emissions." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1564756659521461.
Full textJermain, Robert F. "Effects of EMF Emissions from Undersea Electric Cables on Coral Reef Fishes." NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/418.
Full textGärskog, Gustav. "NUMERICAL CALCULATION METHOD FOR MAGNETIC FIELDS IN THE VICINITY OF CURRENT-CARRYING CONDUCTORS." Thesis, Uppsala universitet, Elektricitetslära, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353338.
Full textWiese, Michelle Kim. "Immune stimulation with short-term exposure to extremely low frequency electromagnetic fields in mice (Mus. musculus)." Thesis, Bloemfontein : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/209.
Full textElectromagnetic fields are present wherever electricity is created. The frequency range of these electromagnetic fields is from extremely low to extremely high. The fields present in domestic areas fall within the extremely low frequency range. These fields are created by domestic electrical appliances and telecommunication. There has been much debate on the effect of exposure to these fields on human health. Research has not yet been able to prove adverse effect of these fields on human health. In fact, the benefits of magneto therapy has been recognized and used for several decades. Recently a specific electromagnetic signal has been under investigation for its ability to stimulate the immune response. This signal is produced by a patented generator, called Immunent Activator. Studies performed with the Immunent Activator signal on farm animals revealed increased feed conversion and decreased intestinal lesions of animals with intestinal infections. Most of the research was performed on fish and fowls and evidence of similar findings in mammals is lacking. In the current study, mice were exposed to the Immunent BV signal for seven days, after which immune cell counts were performed and compared to the immune cell counts of a control group of mice which received no electromagnetic exposure. It was found that the T-lymphocyte population of immune cells in the exposed group of mice was statistically significantly higher than that of the control group. The neutrophil count was statistically significantly lower in the exposed group compared to the control group. These findings revealed evidence of immune stimulation in the mice which were exposed to the Immunent Activator signal. Suggestions for further research could be made with regard to specific mechanisms of immune stimulation. The findings of this and other related studies hold benefits for the farming and health industry.
Sivaraman, Nimisha. "Design of magnetic probes for near field measurements and the development of algorithms for the prediction of EMC." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT082/document.
Full textAs the number of components in a confined volume is increasing, there is a strong demand for identifying the sources of radiation in PCBs and the prediction of EMC of electronic circuits. Electromagnetic near field scanning is a general method of identifying the radiating sources in a PCB. The first part of the thesis consists of the design and characterization of printed circuit magnetic probes with high sensitivity and high spatial resolution. Conventional probes based on microstrip and coplanar configuration is studied. As the length of the transmission line connected to the probe increases, the probe output contains noise due to common mode voltages which is many induced by the electric field. In order to suppress the voltage induced due to the electric field, a shielded magnetic probe is designed and fabricated using low cost printed circuit board (PCB) technology. The performance of the passive probe is calibrated and validated from 1MHz – 1GHz. The shielded probe is fabricated on an FR4 substrate of thickness 0.8mm and consists of 3 layers with the signal in the middle layer and top and bottom layers dedicated to ground planes. The aperture size of the loop is 800µm x 800µm, with an expected spatial resolution of 400 µm. The high sensitivity of the probe is achieved by integrating a low noise amplifier at the output of the probe, hence making an active probe. The performance of the shielded probe with a different length of transmission lines is made to study. When the probe has to be operated above 100MHz, it is found that the transmission lines connected to the probe should be short (around 1.5cmm). For frequencies below 100MH, the length of the lines can be up to 12cm. A three-axis probe which is able to measure the three components of the magnetic field is also designed and validated by near field scanning above a standard wire over the ground structure.In The second part, the inverse transmission line matrix method (Inv-TLM) method is used reconstruct the source distribution from the near field scan (NFS) data above a single in plane on the PCB. Even though the resolution of reconstruction depends on the wavelength and the mesh parameter, the inverse propagation increases the width of the reconstructed wave. As this method is found to be ill posed and results in multiple solutions, we have developed a new method based on the two-dimensional cross-correlation, which represents the near field scan data in terms of the equivalent electric currents of the dipole. With the new method, we are able to identify and locate the current sources in the PCB and are represented by an equivalent source. The method is validated for the current sources with different orientations. The simulated near field data using CST microwave studio is used to validate both the methods. The radiated far field from these equivalent sources is compared with the simulated fields
Lyttkens, Peter. "Electromagnetic field and neurological disorders Alzheimer´s disease, why the problem is difficult and how to solve it." Thesis, Uppsala universitet, Logopedi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-380074.
Full textSollitto, Ciliane Matilde. ""Efeitos clastogênicos em Tradescantia (Trad-MCN) induzidos por campos magnéticos de freqüência extremamente baixa (ELF)"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-19102005-131652/.
Full textThe clastogenic effects of the extremely low frequency magnetic fields (ELF) were investigated using Tradescantia pallida micronucleus assay (Trad-MCN). Inflorescences exposed during 8 hours to doses of ELF-416mG, 833mG, e 4160mG, prescribed for public and occupational exposures, showed increased frequency of micronuclei in the group receiving the highest dose (10.32±7.31), compared with others (p=0.00, Kruskal-Wallis). We demonstrated that an ELF exposure induces DNA damage in Tradescantia. This results encourages the use of this assay to evaluate the usefulness of this monitor in field studies, helping to characterize the role of ELF in causing neoplasm
Chupáč, Michal. "Skener elektromagnetických polí a jeho využití při měření elektromagnetické kompatibility." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220301.
Full textSlach, Petr. "Pracoviště pro zkoušky odolnosti zařízení vůči silným vysokofrekvenčním elektromagnetickým polím." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218038.
Full textMontaño, Raul. "The Effects of Lightning on Low Voltage Power Networks." Doctoral thesis, Uppsala University, Division for Electricity and Lightning Research, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6236.
Full textThe present society is highly dependant on complex electronics systems, which have a low damage threshold level. Therefore, there is a high risk of partial or total loss of the system’s electronics when they are exposed to a thunderstorm environment. This calls for a deep understanding on the mechanism related to the interaction of lightning generated electromagnetic fields with various large distributed/scattered systems. To accurately represent the interaction of lightning electromagnetic fields with electrical networks, it is necessary to have return stroke models capable to reproduce the electromagnetic field signatures generated by a lightning flash. Several models have been developed in the recent past to study the field-to-wire coupling mechanism. The most popular, simple and accurate among the available models is the Agrawal et al. model. On the other hand, ATP-EMTP is a well-known transient simulation package widely used by power engineers. This package has various built-in line models like Semlyen, Marti and Noda setups. There is a difficulty in applying the Agrawal et al. model with the built-in line models of ATP-EMTP, as the voltage source due to the horizontal component of electric field in Agrawal et al. model is in series with the line impedance and not in between two transmission line segments. Furthermore, when the electromagnetic field is propagating over a finite conducting ground plane, the soil will selectively attenuate the high frequency content of the electromagnetic field; causing a change in the field wave shape. A finite conducting ground will also produce a horizontal field component at the ground level. Several approximations are available in the literature to obtain the horizontal electric field; namely the wave-tilt and the Cooray-Rubinstein approximation. Consequently, it is important to investigate the change on the induced voltage signature when the power line is located over a finitely conducting ground. Additionally, to provide protection from lightning induced transients it is necessary to use Surge Protective Devices (SPDs) capable of diverting the incoming transients and provide protection level necessary to avoid damage in the equipment. However, standard test procedures of the SPDs do not take into account sub-microsecond structure of the transients. Therefore, to provide the required protection level to sensitive equipments connected to the low voltage power network, it is essential to understand the response of SPDs subjected to high current derivative impulses. This thesis is aimed to investigate the research problems as addressed above. Special attention will be given to a new proposed return stroke model, a simple circuit approach for efficient implementation of Agrawal et al. model using ATP-EMTP, the effect of the soil conductivity on the lightning induced overvoltage signatures and the response of surge protective devices subjected to high current derivative impulses.
Op, 'T Land Sjoerd. "La modélisation de l’immunité des circuits intégrés au-delà de 1 GHz." Thesis, Rennes, INSA, 2014. http://www.theses.fr/2014ISAR0029/document.
Full textElectromagnetic Compatibility (EMC) is the faculty of working devices to co-exist electromagnetically. In practice, it turns out to be very complex to create electromagnetically compatible devices. The weapon to succeed the complex challenge of creating First-Time-Right (FTR) compatible devices is modelling. This thesis investigates whether it makes sense to model the conducted immunity of Integrated Circuits (ICs) beyond 1 GHz and how to do that. If the Printed Circuit Board (PCB) traces determine a PCB's radiated immunity, it is interesting to predict their coupling efficiency and to understand how that depends on the trace routing. Because full-wave solvers are slow and do not yield understanding, the existing Taylor cell model is modified to yield another 100 times speedup and an insightful upper bound, for vertically polarised, grazing-incident plane wave illumination of electrically long, multi-segment traces with arbitrary terminal loads. The results up to 20 GHz match with full-wave simulations to within 2.6 dB average absolute error and with Gigahertz Transverse Electromagnetic-cell (GTEM-cell) measurements to within 4.0 dB average absolute error. If the conducted immunity of ICs is interesting above 1 GHz, a measurement method is needed that is valid beyond 1 GHz. There is no standardised method yet, because with rising frequency, the common measurement set-up increasingly obscures the IC's immunity. An attempt to model and remove the set-up's impact on the measurement result proved difficult. Therefore, a simplified set-up and extraction method is proposed and a proof-of-concept of the automatic generation of the set-up's PCB is given. The conducted immunity of an LM7805 voltage regulator is measured up to 4.2 GHz to demonstrate the method. Except for a general trend of rising frequencies, there is only little concrete proof for the relevance of IC immunity modelling beyond 1 GHz. A full-wave simulation suggests that up to 10 GHz, most energy enters the die via the trace. Similarly, the radiated immunity of a microstrip trace and an LM7805 voltage regulator is predicted by concatenating the models developed above. Although this model neglects the radiated immunity of the IC itself, the prediction corresponds with GTEM-cell measurement to within 2.1 dB average absolute error. These experiments suggest the most radiation enters a PCB via its traces, well beyond 1 GHz, hence it is useful to model the conducted immunity of IC beyond 1 GHz. Therefore, the extension of IEC 62132-4 to 10 GHz should be seriously considered. Moreover, the speed and transparency of the modified Taylor model for field-to-trace coupling open up new possibilities for computer-aided design. The semi-automatic generation of lean extraction PCB could facilitate model extraction. There are also critical remaining questions, remaining to be answered
Cholachue, Ngounou Christel. "Caractérisation des blindages électromagnétiques des câbles et faisceaux aéronautiques." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR025.
Full textDuring the last decade, the proliferation of on-board leisure activities in the new aircrafts have been growing exponentially. In the airplane like A380, each seat integrates several functions (video games, music, etc. ..) Additionally, each function must be connected using at least one electric cable. This system requires a significant number of kilometers of cables to establish all the on-board electrical connections. Furthermore, for reasons of safety and security related to mechanical, hydraulic or pneumatic functions, the wiring EMC requirements associated to the massive progressive electrification becomes considerably stricter. The coexistence of kilometer lengths of cables system in such a small space has increased the requirements in terms of electromagnetic (EM) shielding. Most of existing numerous methods for analyzing the shielding of cables and harnesses are limited in terms of computation speed, design process and in accuracies for the multiport systems analysis. Moreover, most of popular simulation and commercial tools are very expensive (for example with license cost can be more than 18K€). The use of commercial tools requires advanced skills and a lot of time to characterize the shielding of cables and harnesses. For example, with a simulation tool like HFSSR from ANSYSR , the computation time may cost approximately 3 hours to create a design model of a braided shields heath. Then, the computed results can be generated during an average simulation time of 20 minutes using a PC equipped with an Intel single-core processor RXeon RCPU E5-1620 v4 @ 3.50 GHz and 32 GB of physical RAM with 64-bit Windows 10. Most of available methods and techniques for characterizing the shielding of aeronautical cables and cable harnesses have shown their limits. For example, most of existing triaxial benches are particularly difficult to deploy for the transfer impedance measurements and they cannot operate beyond 100 MHz. The present PhD thesis aims to overcome these technical limits. Doing this, an original analytical method is developed for extracting S-parameters from multiport systems under fast computation speed and design process. An innovative methodology of EMC modelling was proposed. The knowledge of S-parameters is helpful to determine the broadband EM intrinsic parameters of the cabling as coaxial system. The developed analytical and semi-hybrid model is based on the unfamiliar formalism using tensorial analysis of networks (TAN) based on the Kron’s method. The model offers an outstanding possibility to analyze complex systems with deep knowledge of physical phenomenal behind the EM shielding. Thanks to the TAN formalism, an innovative method of circuit theory has been developed to determine the shielding efficiency (SE) of shielded cable. The feasibility of this multiport S-parameter approach was verified with the consideration of EM coupling between a nude cable constituting an internal conductor and a braided cable placed in parallel. More importantly, an advanced study of shielding efficiency (SE) with respect to the EM coupling configuration between a shielded coaxial cable and a loop probe is performed. Substantially, it was noteworthy that the TAN formalism provides an illuminating know-how on the theoretical, numerical and experimental analyses of cables and bundles EM shielding, and transfer impedances of the shielding sheath. Moreover, the TAN modelling effectiveness was confirmed with different applications with computation time which does not exceed milliseconds. Finally, the TAN model was also used to develop a SE characterization bench for tubular EM shielding structures up to 300 MHz. Emphatically, broadband SE and transfer impedance results in good correlation between 3D simulations and measurements were obtained
Huang, Ting-yi, and 黃婷意. "Are Extremely Low Frequency Electromagnetic Fields(ELF-EMF) Safe? Deconstructing Risk Perceptions of the ELF-EMF Controversy in Taiwan." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/09444573038192213245.
Full textPo-ChangHuang and 黃佰璋. "Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF): From variations in worldwide prevalence to effects of individual EMF exposure." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/6shwe3.
Full text國立成功大學
環境醫學研究所
106
Electromagnetic hypersensitivity refers to health effects attributed to electromagnetic field (EMF) exposure. These symptoms have been officially named “idiopathic environmental intolerance attributed to electromagnetic fields” (IEI-EMF) by the World Health Organization. Because of the growing use of cell phones, IEI-EMF has become a global public health concern. A nationwide telephone survey in 2007 in Taiwan showed that the prevalence rate of IEI-EMF was 13.3%, which is higher than rates in previous studies. We conducted a survey using the same method, and found that the rate had declined to 4.6% in 2012. We also found a declining global prevalence in our literature review. Because media reports may encourage readers to attribute their symptoms to EMF, this change might be related to media coverage. We searched for articles indexed in the largest newspaper database in Taiwan to evaluate the association between media coverage and the prevalence of IEI-EMF. The number of newspaper articles related to EMF and IEI-EMF increased from 2005 to 2007 and then has been decreasing until 2012, which is compatible with the change in the prevalence of IEI-EMF. We also assessed the effects of other potential affecting factors, such as the density of mobile phone base stations, the number of mobile phone users, total mobile phone calling time, and the number of text messages sent through mobile phones. We found that all of these potential factors increased in Taiwan from 2007 to 2012. The result of an environmental EMF exposure study cannot be used to explain the condition of individual exposure. Therefore, we conducted a double-blind provocation study to test whether EMF exposure affects blood pressure (BP) and heart rate variation (HRV), and to verify whether IEI-EMF sufferers are able to accurately discriminate between sham and real EMF exposures. 58 self-reported IEI-EMF sufferers and 92 controls were exposed to base station-like signal in a double-blind and randomized experimental procedure. The BP and HRV of individuals in both groups remained unaffected by EMF exposure. Neither the IEI-EMF group nor controls could accurately identify the provocation status of their sessions. Our study indicated that short-term mobile phone signal exposure does not affect BP and HRV and that none of the participants could accurately detect EMF exposure. In conclusion, the results of our study support the hypotheses that risk perception of EMF might be affected by media reports, and that exposure to short-term, low intensity, base station-like EMF does not affect BP and HRV.
Peng, Kuang-Ping, and 彭光平. "Study of Miniature EMP Electromagnetic Field Sensors." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/3nxy7f.
Full text國立臺北科技大學
機電整合研究所
93
A B-dot sensor is designed for measuring magnetic pulse field. The major characteristic of the sensor uses a half cylinder loop which is formed by a flexible print circuit board with two gaps and two 100 ohm transmission lines etched in the copper. The half cylinder loop sited on a substrate with dielectric constant greater than 1. The front side of the substrate has a 100 ohm transmission line and the ground plane. The back side of the substrate is ground plane. By impedance matching of transmission lines, the SMA terminal connects two transmission lines as output. Because using the flexible print circuit board formed the half cylinder loop, the radius can be reduced a lot. So the sensor’s measurement range can be raised a lot. Comparing with the other B-dot sensor that we knew, volume of the proposed sensor is reduced a lot and sensitivity still can be acceptable. This thesis also improved the performance of the D-dot sensor that we developed before. The developed sensor can measure higher frequency and use another structure that we didn’t see before to fabricate the sensor. The merit of developed sensor is cost down and easy to be fabricated.
Yen, Ching-Hua, and 嚴景華. "Electromagnetic Field Scanning System for EMI Measurement of Printed Circuit Board." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/64023599736119058138.
Full text國立成功大學
電機工程學系碩博士班
94
This thesis presents the system of measuring electromagnetic interference on the printed circuit board, which is mainly composed of the scanning sub-system and the automated test equipment(ATE) sub-system. In scanning sub-system, the scanner is as measuring platform of the PCB. In addition the array probes are made up of the T type microstrip antenna as component for signals measuring, according to the array of 2 x 12 placed, each probe distributes in the square area of 15 mm x 15 mm; the array probes connect to spectrum analyzer by the broadband amplifier. The automated test equipment sub-system, fulfills the probes automatic switching and moving, controls filtering and scanning frequency of spectrum, and receives data from spectrum. Finally, it displays chart of space distributing on the electromagnetic interference of the printed circuit board. The experimental results verify the purpose of position measuring is achieved.
Musumpuka, Remmy. "The association between VLF and ELF chorus emissions and electron precipitation." Thesis, 2009. http://hdl.handle.net/10413/8311.
Full textThesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.
Sunitha, K. "Coupling Of Electromagnetic Fields From Intentional High Power Electromagnetic Sources With A Buried Cable And An Airborne Vehicle In Flight." Thesis, 2013. http://etd.iisc.ernet.in/handle/2005/2620.
Full textRao, M. Mohana. "Electromagnetic Interference And Compatibility Studies In A Gas Insulated Substation During Switching Operations." Thesis, 2005. http://etd.iisc.ernet.in/handle/2005/1483.
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