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Dažniausiai patiriami sveikatos sutrikimai buvo šilumos pojūtis aplink ausį, odos niežėjimas aplink ausį, odos paraudimas bei galvos skausmas. Vertinant naudojimosi įpročių ir sveikatos būklės sąsajas, nustatyta, kad kalbėjimas mobiliuoju telefonu daugiau nei 1 valandą per parą lėmė beveik 2,9 karto, o mobiliojo telefono nešiojimas arti kūno net 6,5 karto didesnę galimybę turėti prastą sveikatą. / The most common experienced health problems are the warmth around the ear, itching of the skin around the ear, skin flushing and headache. Assessing the links between the mobile phone using habits and health status we found that speaking on mobile phone for more than 1 hour per day resulted in almost 2.9 times, and carrying a mobile phone close to the body even 6.5 times higher chance to have poor health.

Thesis (PhD.(Reproductive Biology)--Faculty of Health Sciences)-University of Pretoria, 2007.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 148-157).

Σκοπός της παρούσης εργασίας είναι να παρουσιάσει τα ηλεκτρομαγνητικά, ηλεκτρικά και μαγνητικά πεδία που δέχεται ο άνθρωπος στην καθημερινότητά του, είτε αυτά παράγονται από φυσικές πηγές όπως είναι ο ήλιος, είτε από τεχνητές πηγές όπως είναι οι ηλεκτρικές συσκευές, η κινητή τηλεφωνία, το ηλεκτρικό δίκτυο κ.ά. Επίσης, παρουσιάζονται οι τρόποι υπολογισμού της έκθεσης του ανθρώπου στα πεδία αυτά και τα πιθανά προβλήματα που παρουσιάζονται στην υγεία του ανθρώπου εξαιτίας της έκθεσης. / Nowadays, human is continually exposed to electromagnetic fields, which are produced by nature or artificial sources which has discovered himself. However, the issue that troubles people is whether their health is affected by these fields or not. In this question have been trying to get answers the scientists, international and governmental organizations by carrying out measurements and scientific researches in order to define the impacts of electromagnetic fields on human’s health and determine the exposition limits to these fields. The target of this work is to present the electromagnetic, electric and magnetic fields which human receives in his daily routine, whether are produced by natural sources like sun or artificial sources like household appliances, mobile phones, electricity etc. Furthermore, are being displayed ways of estimation of human’s exposure to these fields and probable repercussions in human’s health owing to this exposure. In chapter two, there is an extensive reference to basic rudiments of fields and their main sources. In addition, are being defined typical magnitudes which are used in specification of electromagnetic fields and human’s exposure to these. In chapter three, are displayed the basic facts of ionizing radiation and its impacts on human. It is mostly presented the main source of ionizing radiation which is ultraviolet radiation of sun and problems which are produced. In chapter four, there is an extensive reference to fields which are produced by household appliances used in people’s houses and how are affect their health. 7 In chapter five, are being presented the basic facts of conveyance and distribution main of Γ.Δ.Ζ and at the same time are defined the impacts which the fields produce when they are near inhabitable areas. In chapter six, are mentioned the problems which can cause mobile phones and generally mobile telephony network which exists in the country through the fields which they produce. In chapter seven, there is a reference to the several types of radar which are used and their results. Whereas, in the next chapter there is a reference to the use of electromagnetic fields in medicine and are being presented radiation doses which we receive through examinations and other problems which can cause. Furthermore, are being presented the exposure limits which take effect in our country and European Union and also the way of analysis of exposure to multiple sources. In chapter eleven, there is a reference to macroscopic and microscopic analysis of exposure to electromagnetic fields. In the last chapter, there are being presented the ways of measurement of human’s exposure to electromagnetic fields with frequency up to 300 GHz.

Electromagnetic induction in the continental Bohai Bay coastal region of China and the island region of Japan is studied with the aid of laboratory analogue models. Detailed model measurements of the electric (Ex, Ey) and magnetic (Bx, By, Bz) field components are presented for an approximately uniform overhead horizontal source field for E- and B-polarizations. With the aid of 2D numerical models, criteria are developed for permitting approximate removal of the coast effect responses in field site measurements in coastal regions. For the Bohai Bay laboratory analogue model, large anomalous in-phase and quadrature model magnetic fields are observed over the Korea-Japan strait for E-polarization, and over the Bohai strait for B-polarization, due to current channelling through the straits. Large responses over the peninsulas in the shallow coastal areas occur at short periods but decrease abruptly with increasing period. The model induction arrows show that the induction in the local Bohai Bay is important primarily at short periods. At long periods, induction in the distant deeper Yellow Sea must be considered in any interpretation of field site measurements. In general, the analogue model results indicate that the effects of peninsulas, straits, bays and the irregularities in the coastlines play an important role in determining the electric and magnetic field responses both on-shore and off-shore for this complex coastal Bohai Bay region. For the Japan laboratory analogue model, electromagnetic field measurements are examined in detail for a series of traverses over Japan, the Korean peninsula, and the coastal region of China and the U.S.S.R. Large anomalous in-phase model magnetic fields are observed over the Korea-Japan strait for E-polarization and over Bohai strait, Tsugaru strait, and La Perouse strait for B-polarization due to off-shore current channelling. The significant responses observed at short periods over the peninsulas in the shallow coastal areas decrease with increasing period. Large gradients in the in-phase BZ are observed over all regions of Japan for E-polarization for both short and long periods due to the effects of induced currents in the surrounding oceans. Thus, induction arrow responses over all regions of Japan show the dominant effects of the ocean. The 2D numerical calculations of EM induction in continental and island coastal regions for an anomalous conductor in the form of an upwelling or a depression in the conductive substratum, show that if the anomalous conductor - ocean separation distance is at least as great as the coast effect response range YR (defined in the present work to be the range where the coast effect |Bz/Byn| has decreased to a value of 0.2), then the coast effect can be removed by vector subtraction to yield a response, approximately that of the anomalous conductor alone. For a given period (in the range 5 -120 min), YR is found to increase with increasing ocean depth, conductive substratum depth, and island width. Further, the dependan.ee on period is found to vary from model to model, but the general trend is for YR to decrease with increasing period, on account of the increasing importance of the underlying conductive substratum through the skin depth effect in the host. Empirical curves are presented showing how the response range depends on the ocean depth, the conductive substratum depth, the island width and the period. Coast effect response values for 3D laboratory analogue models are employed to approximately remove the geomagnetic coast effects in field measurements for some coastal sites in the Bohai Bay continental region of China and the island regions of Japan. The validity of the subtraction is examined for several models of conductive anomalies at sufficiently large anomalous conductor - ocean ranges to satisfy the response range criteria developed for 2D numerical models. The resulting interpretation of field site measurements in complex coastal regions is discussed. With the coast effect removed though subtraction of the model arrows from field site results available in the Bohai Bay region, the resulting difference arrows indicate a N-S striking conductor to the west of Bohai Bay. These difference arrows, as well as the 2D numerical calculations, support the premise of such a conductor, in the form of an upwelling in the conductive substratum (with conductivity 0.5Sm-1 at 80 km depth), situated at about 150 km from the Bohai Bay coastline to account for the field site observations. A comparison of laboratory analogue model and field site MT results at two sites west of Bohai Bay shows that the analogue model apparent resistivities are about an order of magnitude greater than the field site apparent resistivities. This result also supports the model of a conductive anomaly, in addition to the conductive substratum at 80 km depth. Laboratory analogue model measurements are employed to subtract the ocean effect in field measurements to yield difference arrow for these complex island regions of Japan ( the Kii Peninsula region, the central Honshu region and the regions of northern Honshu, Hokkaido and Tsugaru strait). These difference arrows as well as the 2-D numerical model result for the Kii Peninsula region, the central Honshu region, and the northern Honshu region support the premise of two conductive anomalies (with conductivity 0.5Sm-1), one beneath the Pacific Ocean and one beneath the Japan Sea at a depth of 30 km. Further, the difference arrows over the entire Japan region suggest that the two conductors roughly follow the general trend of the island arc, and eventually may be connected by an E-W striking conductor beneath Tsugaru strait to the north. / Graduate

Orientador: Vitor Baranauskas / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-05T19:00:17Z (GMT). No. of bitstreams: 1 Garcez_ScheilaGuedes_M.pdf: 4340903 bytes, checksum: dea029add06ff470ae4ab6fa9dfd28de (MD5) Previous issue date: 2005 / Resumo: Este trabalho apresenta subsídios para uma análise preliminar dos efeitos da interação de campos eletromagnéticos com alguns tipos de tecidos, biológicos. A motivação está na necessidade da avaliação de tais efeitos tendo em vista a da grande difusão na utilização de aparelhos celulares. Nese sentido, os campos analisados estão nas freqüências de 800- 900 e 1800 MHz e nas potências de 600. 250 e 125 mW, respectivamente, que representam valores efetivamente utilizados, principalmente pela tecnologia digitai GSM (Global System for Mobile Communication). O método utilizado roi o FDTD. (Finite-Difference Time-Domain) implementado no software Matlab e os resultados de SAR (Specific Absorption Rate) foram obtidos e comparados com os dado:-publicados por algumas agendas reguladoras / Abstract: This work presents the basis for a primary analysis concerning the effects of iteraiton between electromagnetic fields and some kinds of biological tissues. The motivation is the evaluation need of such effects observing the great diffusion of mobile phones. Therefore, the analyzed fields are in the frequencies of 800. 900 and 1800 MHz with output power of 600, 250 and 125 mW. respectively, which correspond to effective!1, used values, most!) for GSM (Global System for Mobile Communication) digital technology. The used method was FDTD (Finite-Difference Time-Domain) and it was implememed using Mat lab software. The results related lo SAR (Specific Absorption Rate; were achieved and compared with the data published by some regulatory agencies / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica

Die dreidimensionale Positionsbestimmung unter Tage ist eine in der bergbautechnischen Praxis häufig gestellte Aufgabe. Die derzeit gebräuchlichen Verfahren basieren überwiegend auf zahlreichen relativen Messungen zwischen Festpunkten an der Erdoberfläche und dem zu bestimmenden Punkt unter Tage. Das hier vorgestellte Verfahren ist ein im geodätischen Sinn absolutes Verfahren. Die Punktbestimmung erfolgt direkt mit Hilfe der Festpunkte über Tage und dem unbekannten Punkt unter Tage. Relative Messungen zu benachbarten Punkten sind nicht notwendig. Die Grundlage des Verfahrens bildet die zeitliche Erfassung transienter elektromagnetischer Felder an einem zu bestimmenden Punkt unter Tage. Die Quellen dieser Felder sind gleichstromdurchflossene Drahtschleifen an der Erdoberfläche, die näherungsweise magnetische Dipole darstellen. Nach Abschalten des Stromes zerfällt das statische Magnetfeld und induziert elektrische Ströme in der leitfähigen Erde. Das transiente Magnetfeld wird unter Tage an einem Punkt für verschiedene Senderpositionen aufgezeichnet. Mit Hilfe eines Inversionsalgorithmus werden letztlich die dreidimensionalen Koordinaten des Messpunktes bestimmt. / Three-dimensional positioning in mines and caves is a common challenge. The methods currently used are based on numerous relative measurements. The method presented here is an absolute procedure in a geodesic sense. The coordinates of the unknown point are directly calculated using the surface points and the point underground. Relative measurements to neighboring points are not necessary. The localization procedure is based on recording transient electromagnetic fields under-ground. They are generated at the surface using direct-current carrying wire loops, which approximately represent magnetic dipoles. After shutoff the static magnetic field decays and induces electric currents in the conductive Earth. The transient electromagnetic field is recorded at an unknown point in the subsurface for different source positions. Finally, the three-dimensional coordinates of this point are reconstructed using an inversion algorithm.

No description available.

Interest In the vertical fault problem for electromagnetic fields has been recently revived by the papers of I. d'Erceville and G. Kunetz (1962) and D. Rankin (1962). In the derivation of his equations Rankin used d'Erceville1s theory which contains some fallacious assumptions. These have been pointed out by J.T. Weaver (1962) and also in this thesis. This thesis follows the lines of mathematical attack first employed by d'Erceville and Kunetz, and later developed by Weaver, in applying the theory of integral transforms to the partial differential equations satisfied by land and sea conductors. The problem of both a vertical fault and also a sloping fault, i.e. 0 < α < 90° where α is the angle of dip of the fault are considered. The results in the general case are Inconclusive, no solution has been found and no solution is suggested. The case of α = 90° has proved to be equally indeterminate, but a solution has been suggested, which, although it has not been proved rigourously, does not appear to violate any physical principles and also seems to represent the field equations on the surface of the land and the sea. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate