O presente trabalho trata do cálculo da força contra eletromotriz em carga de uma máquina síncrona com ímãs na superfície do rotor (cuja forma de onda de força contra eletromotriz é não senoidal) sendo esta alimentada por correntes de fase cujas forma de onda são quadradas. Para conduzir esta investigação e calcular a força contra eletromotriz da máquina em estudo, faz-se uma revisão sobre o Método da Permeabilidade Fixa, método este que permite a linearização do ponto de operação da máquina. Dessa forma, as simulações são conduzidas por meio do método dos elementos finitos e do Método da Permeabilidade Fixa, levando-se em conta a forma de onda da corrente de alimentação. Atenção especial é dada ao modo que se analisa o fluxo concatenado e a forma de obtenção da força contra eletromotriz uma vez que as formas de onda do fluxo concatenado sofrem variações abruptas a cada 60º elétricos. Além destes parâmetros, analisa-se também cada uma das parcelas do torque eletromagnético, i.e., torque mútuo, torque de relutância e torque de borda, sendo realizado ao final do trabalho, uma comparação entre a soma da estimativa de cada parâmetro com o valor do torque eletromagnético obtido por meio de uma simulação não linear. / This work deals with the assessment of a surface mounted magnet synchronous machine\'s parameters (whose back-EMF is approximately trapezoidal) and that is fed by an ideal square current waveform. In order to investigate and describe each machine\'s parameter, a review on Frozen Permeability Method is presented. Some simulation by means of finite element method with the aid of Frozen Permeability Method are carried out taking into account that the machine is fed by an ideal square current waveform. The results for flux-linkage wave-form and back-EMF waveform are shown and analyzed. A special attention is given to back-EMF calculation since the linkage flux of each phase has an abrupt change every sixty electrical degrees due to the phase commutation. In addition, an attention is given to each torque component on load condition, i.e., mutual torque, reluctance torque, cogging torque and a comparison between the electromagnetic torque and the summation of these components.

Environmental assessments and authorisations surrounding project level developments are often made in isolation, without consideration of the regional or strategic context within which individual developments are done. This research investigates the quality of Environmental Management Frameworks (EMF) as strategic environmental instrument. EMF is a unique South African instrument that was first conceptualised in 1989, enacted in 2006 and updated in 2010. EMFs were developed to map environmental sensitivity to aid the screening out of undesired developments in sensitive environments and to minimise unnecessary project level assessments in preferred development areas. EMFs form an important link between environmental assessment (EA) processes and planning strategies such as Spatial Development Frameworks (SDFs) and Integrated Development Plans (IDPs), due to their spatial output of environmental sensitivity maps and their ability to feed strategic assessment processes required by SDFs. They have a legal mandate which ensures their assimilation and use. This research uses a multiple case study approach to review seven EMF documents for their quality. The quality aspects identified are the process, methodology and documentation components, using the printed EMF documentation as primary information source. Quality review criteria were subsequently developed to investigate these inputs, using the legal mandate of EMF as basis. Each case was rated for compliance with the quality criteria using a six–level rating schedule. Further analyses were made by comparing the performance of cases against one another. Public participation emerged as the weakest component of EMF practice, while aspects of sensitivity analysis also performed weaker than other aspects. More focus is required on aligning scales and resolutions of map inputs, mapping methods and general integration of spatial data, especially those of adjoining districts. The need to substantiate a rationale for buffer determination also requires further refinement. The practice of conducting EMF is well established and it can be valuable in sustainable development planning and decisionmaking. Recommendations to enhance the sustainability outcomes and hence effectiveness of this instrument are made, as well as future research objectives for increasing its utility. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.

Environmental assessments and authorisations surrounding project level developments are often made in isolation, without consideration of the regional or strategic context within which individual developments are done. This research investigates the quality of Environmental Management Frameworks (EMF) as strategic environmental instrument. EMF is a unique South African instrument that was first conceptualised in 1989, enacted in 2006 and updated in 2010. EMFs were developed to map environmental sensitivity to aid the screening out of undesired developments in sensitive environments and to minimise unnecessary project level assessments in preferred development areas. EMFs form an important link between environmental assessment (EA) processes and planning strategies such as Spatial Development Frameworks (SDFs) and Integrated Development Plans (IDPs), due to their spatial output of environmental sensitivity maps and their ability to feed strategic assessment processes required by SDFs. They have a legal mandate which ensures their assimilation and use. This research uses a multiple case study approach to review seven EMF documents for their quality. The quality aspects identified are the process, methodology and documentation components, using the printed EMF documentation as primary information source. Quality review criteria were subsequently developed to investigate these inputs, using the legal mandate of EMF as basis. Each case was rated for compliance with the quality criteria using a six–level rating schedule. Further analyses were made by comparing the performance of cases against one another. Public participation emerged as the weakest component of EMF practice, while aspects of sensitivity analysis also performed weaker than other aspects. More focus is required on aligning scales and resolutions of map inputs, mapping methods and general integration of spatial data, especially those of adjoining districts. The need to substantiate a rationale for buffer determination also requires further refinement. The practice of conducting EMF is well established and it can be valuable in sustainable development planning and decisionmaking. Recommendations to enhance the sustainability outcomes and hence effectiveness of this instrument are made, as well as future research objectives for increasing its utility. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.

O presente trabalho trata do cálculo da força contra eletromotriz em carga de uma máquina síncrona com ímãs na superfície do rotor (cuja forma de onda de força contra eletromotriz é não senoidal) sendo esta alimentada por correntes de fase cujas forma de onda são quadradas. Para conduzir esta investigação e calcular a força contra eletromotriz da máquina em estudo, faz-se uma revisão sobre o Método da Permeabilidade Fixa, método este que permite a linearização do ponto de operação da máquina. Dessa forma, as simulações são conduzidas por meio do método dos elementos finitos e do Método da Permeabilidade Fixa, levando-se em conta a forma de onda da corrente de alimentação. Atenção especial é dada ao modo que se analisa o fluxo concatenado e a forma de obtenção da força contra eletromotriz uma vez que as formas de onda do fluxo concatenado sofrem variações abruptas a cada 60º elétricos. Além destes parâmetros, analisa-se também cada uma das parcelas do torque eletromagnético, i.e., torque mútuo, torque de relutância e torque de borda, sendo realizado ao final do trabalho, uma comparação entre a soma da estimativa de cada parâmetro com o valor do torque eletromagnético obtido por meio de uma simulação não linear. / This work deals with the assessment of a surface mounted magnet synchronous machine\'s parameters (whose back-EMF is approximately trapezoidal) and that is fed by an ideal square current waveform. In order to investigate and describe each machine\'s parameter, a review on Frozen Permeability Method is presented. Some simulation by means of finite element method with the aid of Frozen Permeability Method are carried out taking into account that the machine is fed by an ideal square current waveform. The results for flux-linkage wave-form and back-EMF waveform are shown and analyzed. A special attention is given to back-EMF calculation since the linkage flux of each phase has an abrupt change every sixty electrical degrees due to the phase commutation. In addition, an attention is given to each torque component on load condition, i.e., mutual torque, reluctance torque, cogging torque and a comparison between the electromagnetic torque and the summation of these components.

This study is focused on grafical modeling of embedded systems using dialects of UML. It provides a brief description of existing profiles. Furthemore it deals with modeling frameworks for the Eclipse platform and describes an implementation of such modeling tool as a part of project Lissom.

This review concentrates on findings described in the recent literature on the response of cells and tissues to electromagnetic fields (EMF). Models of the causal interaction between different forms of EMF and ions or biomolecules of the cell will be presented together with our own results in cell surface recognition. Naturally occurring electric fields are not only important for cell-surface interactions but are also pivotal for the normal development of the organism and its physiological functions. A further goal of this review is to bridge the gap between recent cell biological studies (which, indeed, show new data of EMF actions) and aspects of EMF-based therapy, e.g., in wounds and bone fractures. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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With the emergence of Fifth Generation (5G) mobile networks, the employment ofhigher frequencies in the millimeter-wave (mmWave) range and the realization of agreat number of beams in 5G radio base stations (RBS) make the electromagnetic (EM)simulation of RBS products very costly in terms of hardware and time requirements.In order to compute the electromagnetic field (EMF) exposure in close proximity of theRBS, more efficient simulation methods are required.The move to mmWave frequencies enables the use of the so-called high frequencymethods for EM simulation with RBS antennas. In this thesis, conventional fullwavesimulation solvers and different implementations of hybridization of highfrequency methods with conventional methods are used with different commercial EMsimulation tools, and their performance is evaluated for the purpose of EMF exposureassessment in close proximity of 5G mmWave RBS.Among all the investigated methods, the hybrid scheme with Finite IntegrationTechnique (FIT) and Shooting and Bouncing Rays (SBR) methods, e.g., thatimplemented in CST Studio Suite 2020, outperforms in terms of hardwarerequirements and time costs, although the accuracy is compromised on the side andbehind the mmWave RBS. The Multilevel Fast Multipole Method (MLFMM), e.g.,that implemented in Altair FEKO 2019, though not a hybrid method, also has goodperformance but requires very large Random Access Memory (RAM), and it cannothandle very exquisite details of RBS. The Finite Difference Time Domain (FDTD)method implemented in EMPIRE XPU can also handle the investigated problemseffciently, but for extremely large problems, its requirements on RAM may become thebottleneck. In the thesis, many other hybrid implementations are also investigated,but it is found that they are not suitable for the EMF exposure assessment in closeproximity of the mmWave RBS with evaluation on a planar area of 0.42 m × 1 m at 28 GHz due to various reasons. / För den femte generationens (5G) mobilnät kommer användningen av millimetervågoroch det stora antalet lober som en radiobasstation (RBS) kan hantera att betydaett kraftigt ökat behov av hårdvara och större tidsåtgång för att göra beräkningarav exponeringen för elektromagnetiska fält nära utrustningen. Därför behövs mereffektiva simuleringsmetoder.Eftersom systemen opererar på millimetervåg-frekvenser kan högfrekvensmetoderanvändas i simuleringen av simuleringen av en RBS. I den här avhandlingenutvärderas konventionella metoder, samt olika hybridmetoder för beräkningenav EMF-exponeringen av millimetervågor i närheten av en RBS. De utvärderadehybridmetoderna är implementerade i olika mjukvaror och blandar användandet avhögfrekvensmetoder och konventionella metoder.Av alla utvärderade metoder fungerar hybridmetoden implementerad med finitaintegralmetoden (FIT) och ”Shooting and Bouncing Rays”-metoden (SBR) i CST bästi termer av vilken hårdvara som behövs för beräkningarna och för tidsåtgången.Dock är noggrannheten i beräkningarna på sidan av och bakom RBSen mindrebra. Multilevel Fast Multipole Method (MLFMM)”-lösaren i Feko i FEKO använderingen hybridmetod men presterar bra, men den kräver mycket RAM-minne och kaninte ta hänsyn till små detaljer i RBSen. Finita differensmetoden i tidsdomänen(FDTD) i EMPIRE kan också användas men dess RAM-krav blir en flaskhals förstora simuleringar. Ytterligare hybridmetoder är undersökta i avhandlingen men medslutsatsen att de inte är användbara (av olika anledningar) för beräkningen av EMFexponeringenfrån en RBS opererandes på frekvensen 28 GHz och över en yta som är0.42 x 1 m.

This study employed multiple assessments, including sleep/resting waking EEG (visual scoring and power spectral analysis) and psychomotor vigilance task, to access effects of varying pulse-modulated microwaves (such as: 'talk', 'listen' and 'standby' mode signals) emitted from a standard mobile phone. The idea was prompted by a finding that the pulse modulation frequencies of mobile phone signals correspond to the frequencies of brain delta and alpha waves. Thereby it is possible the brain is able to recognize and respond to the low-frequency components of the mobile phone signals. Supporting evidence comes from repetitively reported EEG alpha and spindle effects of the 2, 8 and 217-Hz pulsed microwave exposure. Furthermore, brain imaging (EEG and PET) studies reveal 'low-frequency pulse-modulated waves' rather than the 'microwave frequency carrier waves' is the sine qua non for inducing these brain physiological effects [Huber et al., 2002, 2005; Regel et al., 2007a]. On the other hand, recent converging evidence, from molecular, behavioural and electrophysiological level, have shown that brain plasticity is a continuous process from waking to sleep and, sleep, a well-defined physiological condition, is 'shaped' by the waking experiences. The latter findings suggest certain sleep EEG features may characterize levels of cortical plasticity during wakefulness. The work presented in this thesis was inspired by these studies and aimed to understand how the real mobile phone signals with different low-frequency pulsing components [such as 'talk' (8, 217 Hz pulsed), 'listen' (2, 8, 217 Hz pulsed) and 'stand by' mode < 2 Hz pulsed)] change human brain electrical activities from waking to sleep. We approached this question based on EEG analysis in two domains: (1) EEG visual scoring; (2) EEG spectral analysis from relaxed waking to the deeper stages of non-NREM sleep. We also looked at the effects on the psychomotor vigilance performance. Results suggest 'talk' and 'Iisten/standby' modes have inverse effects on the distinctive thalamo-cortical oscillation modes and may thus impart inverse effects on their sleep structures. The implications of this study are of practical importance as it suggests the thalamo-cortical oscillations can be modulated by synchronizing rTMS/tDCS/DBS and sleeplwaking EEG. This concept may be applied to modulate the brain oscillation modes for enhancing sleep-dependent brain plastiCity or information processing.